Effects On Coordination Of "Boll--Leaf System" With Different Seed Granularity

With insect-resistant transgenic Bt gene cotton 33 variety as experiment material, characteristics of "boll-leaf system" were researched on three different seed granularities: large-size and fullness (Treat I); large-size and unfullness (Treat II); small-size and fullness (TreatIII). This study aimed to find out the effect of different seed granularity on main organs' growth, development and its physiological characteristics, and on the coordination of "boll-leaf system". The research result would help to provide scientific criterion for evaluating seed quality and selecting suitable seed for cotton production. The results were as follows:Seed size didn't affect the germination ratio. But the germination rate of small-size seed was faster than that of large-size seed. Unfullness seed wasn't suitable to sow because of the lower germination ratio. The plants of Treat I grew high and strongly; TreatIII were puny; the plants of Treat II had the lowest germination ratio and mediacy seedling situation. Treat I had entered reproductive growth stage earlier so that the quantity of fruit branches and buds was larger than other treatments. As to the dry matter accumulation, the whole plant, vegetative organ and reproductive organ had the same trend: Treat I >Treat II >TreatIII. The dry matter weight of three Treats all had obvious difference in the beginning vegetative growth period and the later reproductive growth period. The net weight of seed cotton and shell in the later growth period was also Treat I >TreatII >TreatIII.This study showed that the seed granularity had some effects on characteristics of leaf-source: higher seed percent was in favor of rapid enlargement of cotton leaf-source area , and the change trend of LAI was Treat I > Treat II > Treatlll. The leaf area of leaf corresponding flowering boll on the six growing boll positions had the same change trend. Function leaves on main stem of Treat I had higher contents of chlorophyll, dissolvable sugar, starch, photosynthesis ratio and lower MDA contents in pre-florescence stage than other treatments. So the physiological function of function leaves on main stem of Treat I was stronger than that of Treat II and Treatlll. Different seed granularity had little effect on the characteristics of fruit branch leaves on the first position, while the effect on the leaves on the third position of fruit branch was obvious. The IAA/ABA value of leaves that correspond with 15-day-old boll on the third position...