Showing 171 results for Yield
A. Moradi, A. Ahmadi , A. Hossein Zadeh,
Volume 12, Issue 45 (10-2008)
Abstract
Drought is a major factor limiting growth and development of crops such as mung bean (Vigna radiate (L.) wilczek) in arid and semi-arid regions of the world. This study was conducted to investigate the effects of different timing and severity of drought stress on physiological traits of mung bean and its relation to grain yield. A field experiment was carried out during 2004 growing season at Experimental Farm of Agriculture College, University of Tehran, Karaj, Iran. The treatments were laid out in a Randomized Complete Block Design (RCBD) with three replications. Plants were exposed to moderate and severe water stresses at either vegetative (VS) or reproductive stages (RS). Physiological traits were measured at the end of vegetative and the middle of pod formation. Generally water stress reduced leaf net photosynthesis rate, stomatal conductance and leaf relative water content at different growth stages. The effects of RS treatments were more severe than that of VS one. Severe VS treatment increased photosynthetic water use efficiency, whereas RS treatments decreased it significantly. However, leaf area index and total dry matter were more responsive in VS compared to RS treatments. VS treatments did not affect harvest index, while RS treatments reduced it significantly. Drought stress also reduced grain yield by 9 and 49 % (relative to control plants) in severe VS and severe RS treatments, respectively. Therefore irrigation is critical during reproductive stage mainly because of the higher demand for photoassimilate. It is concluded that to maximize mung bean grain yield in arid and semi-arid areas, appropriate watering should be practiced across all phenological stages in general, and during reproductive stage in particular.
B. Hatami, J. Khajehali, M. R. Sabzalian,
Volume 12, Issue 45 (10-2008)
Abstract
Safflower having oil with high unsaturated fatty acids is a very valuable plant. However the sensitivity of safflower to some pests as safflower fly (Acanthiophilus helianthi), particularly in drought stress conditions has limited its production. In order to evaluate the effect of drought stress on population density and damage of important safflower pests, especially safflower fly, an experiment was conducted in the field using 5 irrigation treatments including 50, 70, 90, 110 and 130 mm evaporation from class A pan in a randomized complete block design with three replications. The local safflower variety used in this study was Isfahan land variety, Kooseh. In each irrigation regime, the half of one plot was locally sprayed by Chlorpyrifos in 2ml per liter of water to be compared with non-sprayed part. During 8 weeks of sampling, population of aphids, Uroleucon carthami, leafhopper, Empoasca decipiens and safflower fly, A. helianthi and also percentage of damaged heads by safflower fly were measured. The results showed that in non-sprayed conditions, the highest safflower fly (2.38 flies per net) and aphid population (165.57 aphids per plant) was observed at 130 mm evaporation regime. Drought stress also decreased (30.23 %) safflower seed yield. Severe drought stress together with non-spaying may increase safflower pests population particularly safflower fly and reduce seed yield. However low level of drought stress (70 mm evaporation from class A pan) may decrease relative number of insects and save irrigation water. Drought stress also decrease the population of leafhopper. In this study, 70 mm evaporation regime was the optimum irrigation treatment regarding lower aphid and fly damage (15.86% damaged heads in non-sprayed condition) and higher safflower seed yield (1687.5 kg/ha in sprayed condition).
H Shariatmadari, Y Rezainejad, A Abdi, A Mahmoudabadi, M Karami,
Volume 12, Issue 46 (1-2009)
Abstract
Many researchers have reported positive effects of converter sludge and slag, two by-products in Isfahan iron melting factory. In this work, the optimum rate of application and the availability of some essential elements (for plant growth) in the converter sludge and slag for corn were investigated. The converter sludge contains about 64% Fe ІІ and ІІІ oxides and some other essential elements for plant growth. The slag also contains 17% iron oxides, 52.8% calcium oxide as well as considerable amounts of some other elements. Treatments included a control, Fe-EDTA foliar spray with 5 in 1000 concentration, application of sludge in 4 levels (L1, L2, L3 and L4 equal to 5.83, 13.33, 20.83 and 26.67 ton/ha, respectively) and application of slag in 4 levels (S1, S2, S3 and S4 equal to 3.20, 7.28, 11.36 and 15.44 ton/ha, respectively) which supply 1, 2, 3 and 4 times as much as soil test recommends, based on AB-DTPA extractable Fe in the soil. Corn (Zea mays) single cross 704 was planted for the experiment. Applications of the two compounds increased the soil extractable Fe and Mn, decreased Mg but the treatment did not change the soil-extractable Zn, Cu and Ca. The corn yield also increased due to the applications of the two compounds and the maximum yield was related to L3, L4, S3 and S4 treatments. The foliar application treated the leaf chlorosis and increased the silage, grain and leaf + stalk yields however, this was not as efficient as sludge and slag application. Also applications of the two compounds increased the Fe, Mn, Zn, Cu, Ca and Mg uptake by corn. The L3 and S3 treatments can be recommended as the proper levels of these compounds as iron fertilizer.
M Noruzi, A Jalalian, Sh Ayoubi, H Khademi,
Volume 12, Issue 46 (1-2009)
Abstract
Crop yield, soil properties and erosion are strongly affected by terrain parameters. Therefore, knowledge about the effects of terrain parameters on strategic crops such as wheat production will help us with sustainable management of landscape. This study was conducted in 900ha, of Ardal district, Charmahal and Bakhtiari Province to develop regression models on wheat yield components vs. terrain parameters. Wheat yield and its components were measured in 100 points. Points were distributed randomly in stratified geomorphic surfaces. Yield components were measured by harvesting of 1 m2 plots. Terrain parameters were calculated by a 3×3 m spacing from digital elevation model. The result of descriptive statistics showed that all variables followed a normal distribution. The highest and lowest coefficient of variance (CV) was related to grain yield (0.36) and thousand seeds weight (0.13), respectively. Multiple regression models were established between yield components and terrain parameters attributes. The predictive models were validated using validation data set (20% of all data). The regression analysis revealed that wetness index and curvature were the most important attributes which explained about 45-78% of total yield components variability within the study area. The overall results indicated that topographic attributes may control a significant variability of rain-fed wheat yield. The result of validation analysis confirmed the above-stated conclusion with low RMSE and ME measures.
F Valimohamadi, M Tajbakhsh, A Saeed,
Volume 12, Issue 46 (1-2009)
Abstract
In order to evaluate effect of planting date and plant density on grain yield, yield components and some quality and morphological traits of chickpea (Cicer arietinum L.), an experiment was conducted at the research center of agricultural and natural resources of west Azerbaijan in Urmia rain-fed research farm during 2005-2006 growing season in a split plot arrangement, based on a completely randomized block design with four replications. The cultivar of chickpea (Qazvin local mass) was planted in three sowing dates (mid November, mid March and mid April) in main plots, and four plant densities (intra row space: 7.5, 10, 15 and 20 cm) representing (45, 34, 23 and 17 plant/m2) in sub plots. Yield, number of pod per plant, seed protein content, plant height, number of secondary branches and 100 seed weight were evaluated. Results indicated that date of sowing had a significant effect on the yield, number of pod per plant and seed protein content but was not significant for plant height, secondary branches and 100 seed weight. Highest number of pod per plant was obtained in mid November sowing (37.69) and high protein content (22.63) in mid March. Different plant density effects were also not significant on yield, plant height, secondary branches and 100 seed weight but the effect of density on the number of pod per plant and seed protein content was significant. Highest number of pod per plant was obtained in the third density (31.5), and highest protein content in the first density (22.31). The results of study indicated that between mid March planting in the density (45 plant/m2) had highest yield (1042.08kg/ha) and protein content compared with the other planting dates.
H Miri,
Volume 12, Issue 46 (1-2009)
Abstract
In order to study changes in morphophysiological traits of wheat cultivars released from 1940 to 2000 in Iran and to determine the association of these traits with grain yield, an RCBD experiment was conducted with 15 wheat cultivars released during past 60 years in Arsanjan (Fars province) in 2006 and 2007. Results indicated that grain yield increased significantly during these 60 years (r=0.912, P<0.01). HI and BY increased significantly with increasing grain yield. The changes in photosynthesis rate were not significant during this period, but transpiration rate and stomotal conductance in recent cultivars increased significantly. Chlorophyll index also increased in new cultivars. Among yield components, grain number per ear increased significantly, but increase in ear number was not significant. Plant height decreased significantly in new cultivars. The results showed that during wheat breeding in Iran, increasing HI, grain number per ear, transpiration rate, stomatal conductance and decreasing plant height had the highest role in wheat yield increase. The role of BY and ear number per area were lower in grain yield increase. It seems that present HI values are near the highest possible value, but the opportunity for increasing grain yield by mean of HI is still possible.
R S.sharifi, A Javanshir, M Shakiba, K Ghasemi Golezani, A Mohamadi, Y Raei,
Volume 12, Issue 46 (1-2009)
Abstract
In order to study yield component and determinate the contribution of stem reserves to corn yield under effect of different densities and interference periods of sorghum, a factorial experiment based on randomized complete block design with three replications was conducted in 2002 on the Research Farm of the Faculty of Agriculture Tabriz University. Experimental factors were sorghum interference at different periods (0,14,28,42 days after corn emergence and also during plant life corn) with three densities (4,8,12 plants m-2). Characteristics of study were yield, yield component and the contribution of stem reserves to corn grain yield. The results showed that with increasing sorghum density and interference, corn yield components (except the number of grain rows) were decreased, due to shading and competition between plants for using available resources. Maximum grain yield and grain number per ear was obtained at pure corn plantation. With increasing sorghum density and interference periods grain yield decreased, and maximum corn yield loss was 38%, which occurred at the highest sorghum density and interference. Dry matter remobilization and contribution of stem reserves were significantly influenced by sorghum densities and interferences in corn grain yield. The highest contribution of dry matter remobilization and stem reserves to corn yield was obtained at maximum density and complete interference of sorghum. The least contribution of reserves was shown in pure corn plantation. This might be related to shading and competition between plants for light and other resources.
M Babaeian, M Haydari, A Ghanbari,
Volume 12, Issue 46 (1-2009)
Abstract
In order to study the effects of foliar micronutrient application under water stress at three stages of growth on proline and carbohydrate concentrations, grain yield and yield components of sunflower (Alster cultivar), a field experiment in split plot design with three replications was conducted in 2007. Alster cultivar was considered under water stress at three stages of growth (heading, flowering and grain filling) as main plot and seven micronutrient treatments, Fe, Zn, Mn, Fe+Zn, Fe+Mn, Zn+Mn and Fe+Zn+Mn, as sub plots. Results showed, water stress at three stages of growth significantly decreased grain yield, biological yield, 1000 weight seeds, cap diameter and cap weight of sunflower (Alster cultivar). The impact of water stress was more pronounced when applied at grain filling. Use of foliar micronutrient increased grain yield in water stress. On the other hand, use of Mn foliar application had the highest positive effect on yield components and grain yield. Free proline and total soluble carbohydrate concentration were increased under water stress at all of the three stages of growth. The highest concentration of these two components was found on the flowering stage. Foliar micronutrient also increased accumulation of the two components.
A Ahmadi, M Jodi, A Tavakoli, M Ranjbar,
Volume 12, Issue 46 (1-2009)
Abstract
The objective of this study was to evaluate some morphological characteristics associated with grain yield potential on 20 bread wheat cultivars under two irrigation and drought stress conditions. The experiments were conducted at Research Farm of Agriculture College, University of Tehran, Karaj during 2001-2003. Twenty bread wheat cultivars were planted as subplots within each irrigation main plots in randomized complete block design with 3 replications. Drought stress was imposed at the end of flowering, and plants were re-watered when they showed signs of wilting, particularly during the morning. The results showed that the interactions between cultivars × year and cultivars × irrigation were significant for the grain yield. The cultivars showed significant differences in grain yield under drought stress condition in 2001-2003. Roshan, M-79-4 and Alvand in 2001-2002 and Azadi, Marvdasht and M-79-17 in 2002-2003 were most productive under drought stress condition, whereas C-79-12, MV-17 and Shahpasand in 2001-2002 and M-79-4, Roshan and Nicknajad in 2002-2003 performed visa versa. Correlation between grain yield and measured traits under irrigation condition was different from drought stress condition, suggesting that grain yield controlling mechanisms operate differently under these conditions. Drought stress caused a reduction in 1000 seed weight of cultivars. High 1000 seed weight and high grain number per ear were accompanied by high grain yield in drought stress and irrigation conditions, respectively. In the present study, clear relationship between grain yield and ear length was not observed.
Z Amiri, J Asghari, Kh Penahi Kord Aghari,
Volume 12, Issue 46 (1-2009)
Abstract
In order to determine the potato cultivars responses to irrigation regimes and fertilizer combinations, an experiment was conducted on Fereidan Research Farm, Isfahan Province in 2003. The trial was designed as split-split plot based on randomized complete block design with three replications. The cultivars (Arinda and Navita) were planted as main plots, and irrigated after 70, 140, 210 mm water evaporation from standard A pan surface that provided optimal watering, mild drought, and severe drought, respectively, as sub plots. Fertilizer combinations including of NPK + Zn, NPK+ Mn, NPK +Zn + Mn and NPK+ Manure were used as sub-sub plots. Results showed that the cultivar Arinda produced higher yield, mean tuber weight and total tuber number. By decreasing the amount of irrigation, the total yield and mean tuber weight were decreased. The highest amount of seed tubers (35-55 mm diameter) and marketable tuber sizes (diameter>35mm) and lowest amount of small size tuber numbers (diameter <35) were obtained in moderate drought. The use of NPK + Zn + Mn and NPK+ Manure produced the highest yield and mean tuber weight. Planting the cultivar Arinda with efficient irrigation is suggested in Isfahan province. Moderate drought is recommended for production of higher amount of seedy tubers. A combination of manure, Mn and Zn fertilizers are also suggested for potato farms of this district.
Z Daneshvar Ran, M Esfahani, M Payman, M Rabiei, H Samie Zadeh,
Volume 12, Issue 46 (1-2009)
Abstract
The effects of tillage methods and residual management on yield and yield components of rapeseed (Brassica napus L. CV. Hyola308) were evaluated after rice harvest. The experiment was carried out during 2004-2005 cropping season in a factorical arrangement of treatments at Rice Research Institute of Iran (RRII) in Rasht, in a Complete Randomized Block Design with three replications. Treatments included tillage in three methods: a) conventional tillage b) minimum tillage, and c) no tillage, and rice residue management in two manners: a) removing residues, and b) not removing residues. Plant traits such as grain yield, oil percentage and yield, plant density, plant height, the lowest pody branch height from soil surface, number of pods per plant, plant and weed dry weight, leaf area index (LAI) and crop growth rate (CGR) were measured. Results indicated that grain yield was affected by the tillage type. Also, the effect of tillage type on plant height, number of pods per plant, the lowest pody branch height from soil surface, and oil yield was significant. The effect of residual management and residual management interaction and tillage were significant on none of the traits except for weed dry weight. Economic analysis indicated that rapeseed planting in a field with rice residual and minimum tillage had a relative advantage of less production cost in spite of nearly 15 percent yield decrease compared to other methods.
S.h Sadeghi, S.h Pourghasemi, M Mohamadi, H Agharazi,
Volume 12, Issue 46 (1-2009)
Abstract
The use of suitable empirical models for estimation of soil erosion and sediment yield is essential because of nonexistence or shortage of associated data in many watersheds. In the present study, the applicability of the USLE and its different versions Viz. MUSLE-S, AOF, MUSLT, MUSLE-E, USLE-M and AUSLE in estimation of storm-wise sediment yield from standard plots installed in dry farming, ploughed and rangeland treatments was evaluated. To conduct the study, the entire input data were collected from plots installed in three replicates in each treatment in Khosbijan Natural Resources Research Station in Arak Township. The models’ estimates were then compared with the observed sediment data for 12 storm events. Contrary to high correlation among different models’ estimates, the models used in estimation of measured sediment data were found inapplicable. However, significant relationship (r=94.4%) and non-significant relationship with correlation coefficients less than 50% were found between MUSLE-E, and MUSLE-S and MUSLE-E estimates and measured data in rangeland, dry farming and ploughed treatments, respectively.
N Pourghasemin, M Zahedi,
Volume 13, Issue 47 (4-2009)
Abstract
This experiment was conducted at the Agricultural Research Station of Isfahan University of Technolgy in 2006 to evaluate the effects of planting pattern and the level of soil moisture on two safflower cultivars. A factorial split plot arrangement was used in a randomized complete block design with three replications. Two planting patternS (flat and bed planting) and two levels of soil moisture (irrigation after 80 and 100 mm cumulative evaporation from Class A pan) were considered as the main factor and two safflower cultivars (IL 111 and Kosseh) as minor factor. Each plot in flat planting consistedof six rows, spaced 25 cm apart with plants 8 cm apart and in bed planting consisted of four rows, spaced 45cm apart with plants 5 cm apart. The duration from planting to button formation, 50% flowering, and 100% flowering stage were significantly shorter in 45cm bed planting than in 25cm flat planting. The duration from planting to all growth stages was less in IL 111, compared to Kosseh cultivar. The level of soil moisture did not affect the duration of any growth stages. Plant height, leaf area index, plant dry matter, number of buttons per plant, number of grains per button, grain weight, and harvest index were higher in flat planting, compared to bed planting. Plant height, plant dry matter, number of buttons per plant, number of grains per button, grain weight, and harvest index were reduced as the level of soil moisture was decreased. Leaf area index and plant dry matter were not significantly affected by the level of soil moisture at 50% flowering stage. Regardless of the level of soil moisture and cultivar, the grain yield was 36% more in flat planting than bed planting. The grain yield was more at higher level of soil moisture and also in Kosseh than in IL 111. The oil percentage and oil yield was higher in flat planting, compared to bed planting and also in Kosseh than in IL 111. The oil percentage was not significantly affected by the level of soil moisture. However, the oil yield was decreased as the level of soil moisture was reduced. The highest amount (1168 kg/ ha) of oil yield was obtained from Kosseh in flat planting and the lowest amount (417 kg/ ha) was achieved from IL 111 in bed planting. The results from this experiment show that to obtain the optimum yield from summer planting in areas with similar conditions to that of this study the 25cm flat planting compared to the 45cm bed planting, and Kosseh compared to IL 111 cultivar seems to be superior.
M.m Majidi, A Arzani,
Volume 13, Issue 47 (4-2009)
Abstract
Sainfoin (Onobrychis viciifolia Scop.) is a perennial legume widely adapted to environmental conditions and has been successfully used as a pasture and hay forage in Iran. This experiment was carried out to investigate yield potential and genetic variation of morphological, agronomic and qualitative traits using 10 Iranian sainfoin populations. The experiment was conducted as a randomized complete block design with four replications ON Research Farm, Isfahan University of Technology. Results indicated that there are significance differences between populations for most of the traits. The estimates of heritabilities for forage yield, number of stem per plant, number of node and qualitative traits were over 50 percent. The high phenotypic and genotypic coefficients of variability for economic traits showed that a broad genetic diversity in this germplasem can be exploited in breeding programs. Significant differences were found among cuts and cut × population interaction for all characters. The third harvest produced 41.6 percent of total hay yield. Evaluation of traits related to forage quality revealed that the highest proportion of leaf to stem belong to Sarab and Oromieh populations (6.28 and 6.82, respectively). Crude protein percentage was significantly different among cultivars and Golpayegan population had the highest value for Crude protein percentage. Feridan, Khonsar and Golpayegan populations produced the highest dry matter yield in the first, second and third cut, respectively. These populations were found as the high potential accessions, which can be used as a source for agronomic and plant breeding research in the region.
A Faraji, H Hatamzadeh,
Volume 13, Issue 47 (4-2009)
Abstract
Development of oil seed crops is the most important aim in our country to achieve self sufficiency. This study was conducted to assess the suitability of oil brassicas species in rain-fed warm areas of Iran. This research was performed for three years in Agricultural Research stations of Gonbad (Golestan). Twenty varieties and hybrids (B. napus, B. rapa, B. juncea ) were compared in RCBD with three replications under rain fed conditions. Each plot had 4 rows 5-meter long. Combined analysis results indicated that there were significant differences at 1% probability level among years and varieties for No. of days to maturity, No. of pod per plant, oil%, oil and seed yield. The highest seed yield was obtained in the 2nd year (2103.48 kg.ha), followed by the 1th and 3rd year (1771.50 and 1575.13 kg.ha, respectively). Namely, year environment factor had a significant effect on the rape seed product. j-98-102.51-5 (B. juncea), Alexandra and comet (Spring B. napus) showed the highest seed yield (2484, 2326 and 2290 Kg.ha, respectively). Regression analysis via step by step method explained that No. of pod per plant and oil percentage had significant positive effects (508.53 and 96.48 respectively) and No. of days to maturity significant negative effect (-78.63) on the seed yield. Factor analysis extracted four factors. Factor loading of the first three eigen values showed that the first three factors explained 98.794%, sum of variance. Rates of first, second and third factors were 45.575%, 36.816% and 16.403%, respectively. The first factor, second factor and third factor were named productivity factor (seed yield and oil yield), sink factor (No. of pod per plant), fixed capital factor (No. of day to maturity and plant height) respectively. Generally, j-98-102.51-5, Alexandra and comet varieties are advisable for Fall planting under rain fed conditions in Gonbad area because they had the highest seed yield and earliness. Also, we can introduce less No. of days to maturity (earliness) and more No. of pod per plant as select index under rain fed conditions in Gonbad.
S.m Ziaee, M Kafi, J Shabahang, H Khazaee, M Soleimani,
Volume 13, Issue 47 (4-2009)
Abstract
Production of halophytes using saline waters and soils, and feeding livestock with them, is one of the most sustainable ways of desert ecosystems conservation and food production for people living in these areas. A field experiment was conducted at Salinity Research Station, Ferdowsi University of Mashhad, in 2007 to evaluate the effect of planting density and harvesting time on oil and protein yield of Kochia. Treatments were arranged as a split-plot based on a randomized complete block design with three replications. Planting density (10, 20, 30 and 40 plants m-2) as assigned to main plots and two dates of harvesting (after 50% flowering and full maturity) constituted the sub-plots. Plant density had a significant effect on grain yield, mean seed weight, harvest index, oil yield, oil content and protein yield at maturity stage. Forage and protein yield were also affected by plant density at the harvest date of 50% flowering. Total dry matter, protein yield and percentage differed significantly between the two harvest dates. The greatest grain yield (2590 kg ha-1) and oil yield (357.7 kg ha-1) were achieved from 20 plants m-2, whereas those from 10 plants m-2 were minimal. Maximum protein yield (3390 Kg ha-1) was obtained from the planting density of 30 plants m-2 at 50% flowering stage. Based on the results of this study, the best qualitative yields for Kochia could be obtained from a planting density of 30 plants m-2 after 50% flowering but one may recommend planting Kochia at 20 plants m-2 for a high grain or oil production.
B Kavoosi, S Eshghi, A Tafazoli,
Volume 13, Issue 48 (7-2009)
Abstract
Overcroping, shading and short growing season can reduce the pool of carbohydrate reserves, and consequently reduce the quality of crop in grapevines. An experiment was conducted in order to study the effects of cluster number and different levels of cane topping on balanced yield and qualitative traits of table grape (Vitis vinifera L.) cv. Askari. The design of experiment was factorial in completely randomized blocks with four replications. Factors included cluster number (Control, 25, 30, 35, 40, 45 and 50 cluster per vine) and cane topping included (Control, removal 1/4, 1/3 and 1/2 length of shoot). Results showed that decreasing the number of cluster to 25-35 per vine, significantly increased %TSS, TSS/TA and pH but with increasing cluster number, these traits were significantly reduced. Thinning treatment to 25 cluster showed significant difference from the viewpoint of %TA compared with untreated control. Also topping treatment significantly increased %TSS, %TA, TSS/TA ratio and decreased % TA compared with untreated control. Reducing the cluster to 25-45 per vine significantly increased cluster weight, however, no significant difference was observed between control and 50 clusters per vine and/or 25 to 50 clusters. Yield per vine was reduced in all treatments in comparison with untreated control. However, no difference was shown between 25 to 35 and or 40 and 50 clusters per vine. According to the results obtained, cluster thinning combined with topping can be recommended for increasing fruit quality and balanced yield of Askari table grapes in cold climate of Cisakht region.
A Esfahani, A Hoseyn Zade, J Asghari, M Naghizadeh, B Rabiee,
Volume 13, Issue 48 (7-2009)
Abstract
In order to evaluate the effects of sulphur fertilizer sources and amounts on growth indices and yield of peanut (Arachis hypogaea L. CV. NC2), a field experiment was conducted in Bandar Kiaashahr, Guilan province, Iran in 2004. The experiment was laid out in a factorial arrangement with two factors including sulphur sources (gypsum and single super phosphate) and sulphur rates (0, 30, 60 and 90 kg.h-1) in a completely randomized block design with three replications. Results showed that sulphur application greatly enhanced peanut growth and yield. The application of 90 kg.h-1 sulphur (in both forms) performed significantly better than the rest. The highest pod yield and grain yield were obtained in 90 kg.h-1 sulphur in gypsum form (6400 and 5200 kg.h-1, respectively). The highest LAI (6.6), CGR (20.2 g.m-2.12GDD-1) and PGR (16 g.m-2.12GDD-1) were obtained in 90 kg sulphur in the form of gypsum after 1142, 1142 and 1289 of accumulation, respectively. According to the results of the present experiment, it could be concluded that sulphur may considerably increase peanut grain yield and yield components. Thus, it could be expected that the application of 90 kg sulphur per hectare in the form of gypsum may result in better growth indices and higher grain yield of peanut.
S Kamli, O Alishah, N Babaian,
Volume 13, Issue 48 (7-2009)
Abstract
To assess adaptability and stability of seed cotton yield in promising cotton genotypes, eight cultivars of cotton (Gukorova, Nazeli–84, Khordad, No: 200, Crema, Tabladila, Beli Izovar and Sepid), along with two controls (Sahel and Varamin), were studied in a completely randomized block design (RCBD) with four replications in six regions of Golestan and Mazandaran provinces in two successive years (2005 & 2006). Combined analysis of variance was done and means comparison of yield was conducted based on Duncan's multiple range test. Sepid, Beli Izovar, Varamin and Khordad varieties were superior for yield, earliness, boll weight and boll number, respectively. The result of combined variance analysis showed that, there are significant differences between genotypes and genotype × environment (G.E) interaction effect. Because of significant G.E interaction effect univariete stability parametric and non-parametric stability methods were used to determine genotype stability. The results of varied methods were different. The 43200 and Sepid cotton cultivars had a specific adaptation and were suitable cultivar for fertile lands in north of country, because of good reaction to production high yield. In contrast, Sahel cultivar with lowest yield had broad stability with non-fertile regions. Overall, three genotypes (Khordad, Tabladila and Gukorova) were determined with suitable stability and moderate yield (general stability) for most locations in north of country.
R Karimizade, B Vaezi, T Hoseyn Por, A Mehraban, H Ghojagh,
Volume 13, Issue 48 (7-2009)
Abstract
Multi-environment trial data are required to obtain stability performance parameters as selection tools for effective cultivar evaluation. The interrelationship among several stability parameters and their associations with mean yield, along with the repeatability of these parameters in consecutive years was the objective of this study. Barley yield data of 18 cultivars, proprietary of Dryland Agricultural Research Institute, evaluated in 12 locations over 2005-2007 in three locations of Iran was used for the combined analysis of variance in three datasets. I: Across locations in a single evaluation year (dataset A), II: Across locations in each of two single evaluation year (dataset B), III: Across all locations in three years (dataset C). For each dataset, cultivar phenotypic variance and other statistics were appropriately partitioned in its components. The interrelationship among the parameters and their associations with mean yield based on Spearman rank correlation was studied in each of the three single evaluation years (dataset A). Rank correlation coefficients were also used as estimates of the repeatability of these stability parameters across two year combinations (dataset B). The parameters 2 σi Shukla and 2 Wi were consistently highly correlated with each other but not with mean yield in all single and pair evaluation years. The parameters bi , 2 Si and CV were consistently highly correlated with each other but not with mean yield in all single and pair evaluation years. Result showed that Shukla variance, Wricke ecovalence, SIPC1 and ASV AMMI stability statistics have high repeatability. Thus it is suggested that more stability statistics especially nonparametric methods be used for determination of repeatability methods.
