Mohammad Rajab Zadeh, Aghafakhr Mirlohi,
Volume 2, Issue 2 (7-1998)
Abstract
Optimum rice population densities and the response of rice yield and yield components to population densities and planting pattern are important factors helping rice producers and researchers to achieve maximum productivity. For this reason, a randomized complete block design experiment was conducted during the summer of 1995 at Isfahan University of Technology Research Farm located at Lavark, Najafabad. Zayandeh-rood cultivar was transplanted with three seedlings per hill at row spacing of 15, 25 and 35 cm and hill spacing of 10, 15 and 20 cm under flooded conditions. Row spacing influenced the plant height significantly at heading and anthesis stages. Wider row spacing, enhanced days to 50% heading and anthesis and consequently grain filling duration and ripening stage coincided with unfavorable conditions at the end of the season, which decreased the percentage of maturity. Although number of tillers per unit area increased, tillers per plant decreased as row spacing was reduced. Narrow row spacing limited vegetative growth after anthesis and thereby growth rate of panicle increased. With reduction of row spacing, without any change in the percentage of full grains per panicle and grain weight, number of panicle per unit area increased but number of grains per panicle decreased. At greater row spacing, grain yield per unit area decreased although grain yield per plant and harvest index increased. Although, effects of hill spacing were similar to those of row spacing, hill spacing usually did not influence plant characters, yield components and grain yield significantly. Stepwise regression and path-coefficient analysis revealed that number of panicle per unit area is the most important yield components. It also showed that indirect effects of panicle per unit area on yield through its association with grain per panicle prevented real effects of grain per panicle on yield. Fifteen × 15 cm spacing produced maximum yield which is probably recommendable for rice production in Isfahan.
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.
