بررسی ویژگی های کیفی دانه ذرت در مراحل مختلف رسیدگی دانه
محورهای موضوعی : بوم شناسی گیاهان زراعی
1 - استادیار دانشگاه آزاد اسلامی واحد فسا
کلید واژه:
چکیده مقاله :
Although production of hybrid corn kernel is low, the value per unit of yield is several limes greater than that of seed grain. The production of hybrid corn kernel is dependent on timely harvest operations that ensure maximum seed quality and yield of inbred parent and hybrid seed. The present research was conducted al the Experimental Farm of the Islamic Azad University of Fasa during summer 2000. The factorial experiment was designed based on complete randomized block design with 3 replications. The factors were time of seed harvest during various stages of kernel maturity and water deficit. There were several harvests from first week to third week of kernel maturity. The beginning of kernel maturity was determined from kernel growth curve and the end of linear grow th phase. Water deficit consisted of control, early and late water deficit after pollination. As the aim of this investigation was to study of corn kernel harvest different times during the stages of kernel maturity and the efTects of water deficit on kernel quality characteristics, kernels of Sc 704 hybrid parent were seeded. Dry matter weight and moisture percentage of kernels and starch and protein percentage of kernel was determined and used for the explanation of germination percentage and vigor changes of the kernels. The results showed that kernel kernel maturity began from seventh week after pollination and last three weeks. Statistical analysis of kernel dry matter weight showed significant effect at 5% probability level during this three weeks of the water deficit. Also early and late water deficit reduced kernel embryo dry matter weight by average 28.92% and 7.53% respectively during kernel maturity. Kernel moisture percentage has shown significant difference only during the first week of kernel maturity. The germination percentage of com kernels produced during kernel maturity stages was determined. The results showed that kernel germination percentage was minimum in control treatment during first week of kernel maturity (27%) and it was maximum (92%) during the third week of maturity. A linear relationship was obtained between germination percentage and kernel embryo dry matter weight in control and late water deficit treatments. Seedling dry matter weight obtained from germination of the first - week seeds was not affected by water deficit.
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