EFFECT OF PLANT DISTRIBUTION AND NITROGEN LEVELS ON GROWTH, YIELD, YIELD ATTRIBUTES AND SOME QUALITY TRAITS OF SUNFLOWER IN FAYOUM PROVINCE

Abstract

The present investigation was carried out to study the effect of six plant distributions and three nitrogen levels on growth, yield, yield attributes and quality of sunflower hybrid Gl OJ. The obtained results indicated that in the first season, highly significant and significant effects were obserwd on plant height at plant age of 70 and 85 days due to plant distributions. Significant effect was also observed on leaf area per plant and chlorophyll (b) at plant age of 55 days for both and on number of green leaves at plant age of 40 and 85 days and on stem diameter after 70 days from planting. Stem dry weight per plant was significantly affected by plant distribution \Vhen plants were 70 and 85 days old but dry weight of plant without root and leaf area index were highly significantly affected at plant age of 85 days. In the second season, plant distributions had a significant effect on stem diameter, leaf area index and chlorophyll (a) after 85, 40 and 55 days from planting, respectively. Highly significant effect was recorded for head diameter at plant ages of 70 and 85 days, stem dry weight at plant age of 85 days as well as dry weight of leaves and carotenoids both at plant age of 55 days all in the second season. Also leaf area index was highly significantly affected by plant distribution when plant was 85 days old in both seasons. Significant effect was observed on head dry weight at harvest, seed and oil yields per feddan in the first season but in the second season, highly significant effect was observed on seed yield as \\•ell as oil and protein yields per feddan. Generally increasing plant density either with decreasing distance between rows or plants increased seed, oil and protein yields per feddan. Distribution A6 (75x15 cm=37333 plants/fed) in the first season and A6 as well as A4 (60x20 cm=35000 plants/fed) in the second season were the best distributions in this respect. In both seasons, plant distribution had no pronounced effect on head dry weight, specific leaf weight, leaf weight ratio, relative growth rate, crop growth rate, seed oil and protein percentage, plant height and head diameter at harvest, seed yield per plant or per head, 100-seed weight and straw yield per feddan. Nitrogen levels had a significant effect on specific leaf weight at plant age of 40 days and leaf weight ratio at plant age of 70 days only in the first season. Highly significant effect due to nitrogen levels was detected on all other growth characters except on leaf area and leaf area index per plant at plant age of 40 days, a significant effect was observed. Crop gr0\\1h rate was highly significantly affected by nitrogen levels at growth intervals of 40-55 and 55-70 days in both seasons while insignificant effects were observed on relati\•e grov.1h rate in both seasons. Nitrogen levels had a highly significant effect on carotenoids, seed oil and protein percentage as well as yield and yield attributes in both seasons. except on head dry \veight at harvest in both seasons and plant height at han•est in the first season a significant and insignificant effects were observed, respecti\•ely. Significant and highly significant effects were recorded on chlorophyll (a) and (b), respectively in the second season only. The rate of 60 kg/feddan improved most of the above mentioned characters. There was no significant effect due to the interaction between plant distributions and nitrogen levels except on stem dry weight per plant at plant age of 85 days, straw and protein yields per feddan, seed oil percentage in 1995 season and 100- seed weight in 1996 season. Highly significant effects were observed only on number of green leaves, head dry weight at plant age of 85 days in 1995 season and stem diameter at plant age of 55 and 70 days in 1996 season due to plant distribution x N levels interaction.