Gh. Khajouei Nejad, H. Kazemi, H. Alyari, A. Javanshir, M. J. Arvin,
Volume 9, Issue 4 (1-2006)
Abstract
This study was conducted to evaluate the effects of four levels of irrigation (irrigation of plants after I1 = 40, I2 =60, I3 = 80 , and I4 = 100mm of evaporation from class A pan) and four plant densities(D1 = 30, D2 = 40, D3 = 50 and D4 = 60 plants/m2) on the seed yield and seed quality in three soybean cultivars(V1=Hobit, V2=Williams and V3=Hill) in a split factorial design, based on the completely randomized blocks, with three replication for two years(2001 and 2002). The Irrigation treatments were assigned to the main plots, and the plant densities and cultivars to the sub plots. Results indicated that soybean seed yield was influenced by the different irrigation and plant density levels in the both years. Irrigation levels I2 produced the highest and I4 the lowest seed yield. It was also revealed that the plant density D3 produced the highest and D1 the lowest seed yields. Among the cultivars under investigation, V2 produced the highest and V3 the lowest seed yield . Seed oil and its protein contents both were affected significantly by the irrigation levels, plant densities and cultivars in both years. The plants receiving I1 treatment had the highest and those having I4, the lowest percentages of seed oil. Changes in the plant densities also affected seed oil and protein content. The plant density of D1 caused the seeds to have the highest oil and lowest protein percentages. However, D4 decreased oil and increased protein percentages. The highest water use efficiency was obtained from I3 and that of the lowest value from I1. The results also indicated that D4 had the highest and D1 the lowest water use efficiencies. Therefore, it could be concluded that the water use efficiency can be increased by increasing the plant density per unit area. The highest efficiency for biological and grain yield belonged to V2 and V1 respectively where as the lowest efficiency for those two mentioned characters belonged to V1 and V3, respectively. However, the treatment I2V2D2 is recommended for higer the seed yield production per unit area.
F. Vafaei, K. Haddad Irani Nejad, P. Talebi Chaichi, M. Valizadeh,
Volume 10, Issue 3 (10-2006)
Abstract
During years 2000 and 2001, biology and population changes of two- spotted spider mite (T. urticae) was studied on five bean cultivars of two species at 25±1ºC temp., 45±4% RH and 15: 9 (L:D) photoperiod, using leaf disks made from 2-, 6- leaf and flowering stages of the plants. The mite mass rearing was carried out on tomato plants under the same environmental conditions and the effects of feeding on 4 cultivars of phaseolus vulgaris namely Chiti Var. Zanjan, Picher, Sunray, Contender and Vigna unguiculata, Var. Kameran as host plants. Biological features as fertility, percentage of egg hatch, duration of embryonic and larval development, percentage were also Studied of lraval mortality, duration of nymphal stages, developmental period from lava to pre- oviposition stages, oviposition period, adult mite longevity, number of progenies, their percentage mortalities, and sex ratios were determined. The results indicated that the two cultivars Chiti Var: Zanjan, Contender, and species Vigna unguiculatat Var. Kameran at 2- leaf stage appeared to be suitable hosts causing higher egg production and hatches, lower embryonic and larval developmental time and lower rate of larval mortality, lower nymphal developmental period, lower duration from larval stage to preoviposition, extended oviposition period and higher adult longevity. In contrast, the cultivars, Sunray and Picker were shown to be unsuitable hosts. Regarding 6- leaf stage, the cultivar Contender and Vigna unguiculatat, were considered as suitable hosts in relation to embryonic developmental time, number of larvae, duration of larval stage, and rate of mortalities, nymphal developmental time and duration from larval stage to pre- oviposition, extended oviposition stage, sex ratio and adult longevity. But the cultivars Chiti, Picker and Sunray appeared to be unsuitable hosts. In relation to the number of eggs and percentage of egg hatch, number of larvae and nymphs, nymphal mortality rates and sex ratio, the cultivars, Picker and Sunray were considered as suitable hosts at their flowering stage but Vigna unguiculatat and Contender were identified as unsuitable ones.
