江西农业学报
江西農業學報
강서농업학보
ACTA AGRICULTURAE JIANGXI
2014年
8期
4-8
,共5页
玉米%光合有效辐射%花期%弱光胁迫%穗粒数%连阴雨
玉米%光閤有效輻射%花期%弱光脅迫%穗粒數%連陰雨
옥미%광합유효복사%화기%약광협박%수립수%련음우
Maize%Photosynthetically active radiation%Flowering stage%Low light stress%Kernel number per ear%Continuous cloudy and rainy days
为明确花期弱光对玉米穗粒数的影响规律，采用人工遮光模拟弱光胁迫，设置抽雄始期和吐丝期持续10 d 60%和90%两个不同遮光强度的弱光处理，研究了花期弱光对雌穗小花受精、结实，干物质积累及其向雌穗分配的影响。结果发现，花期弱光胁迫导致玉米地上部总干物质日增重量降低，干物质分配到雌穗的比例减少，雌穗生长变慢，受精结实率降低，影响程度随遮光率的增加而增大。抽雄始期60%和90%遮光处理10 d后恢复自然光照结实率较处理结束时的受精率均明显提高，吐丝期60%和90%遮光处理10 d后恢复自然光照结实率较处理结束时的受精率降低和持平。抽雄始期光照不足导致穗粒数较对照下降57%~91%；吐丝始期光照不足导致穗粒数较对照下降43%~81%。无论对于抽雄始期还是吐丝期，遮光处理期间的日平均光合有效辐射强度在穗粒形成中作用最大，其次为处理期间的地上部总干物质日增重。对于吐丝期，处理期间的日平均温度对穗粒数也具有直接的正效应。
為明確花期弱光對玉米穗粒數的影響規律，採用人工遮光模擬弱光脅迫，設置抽雄始期和吐絲期持續10 d 60%和90%兩箇不同遮光彊度的弱光處理，研究瞭花期弱光對雌穗小花受精、結實，榦物質積纍及其嚮雌穗分配的影響。結果髮現，花期弱光脅迫導緻玉米地上部總榦物質日增重量降低，榦物質分配到雌穗的比例減少，雌穗生長變慢，受精結實率降低，影響程度隨遮光率的增加而增大。抽雄始期60%和90%遮光處理10 d後恢複自然光照結實率較處理結束時的受精率均明顯提高，吐絲期60%和90%遮光處理10 d後恢複自然光照結實率較處理結束時的受精率降低和持平。抽雄始期光照不足導緻穗粒數較對照下降57%~91%；吐絲始期光照不足導緻穗粒數較對照下降43%~81%。無論對于抽雄始期還是吐絲期，遮光處理期間的日平均光閤有效輻射彊度在穗粒形成中作用最大，其次為處理期間的地上部總榦物質日增重。對于吐絲期，處理期間的日平均溫度對穗粒數也具有直接的正效應。
위명학화기약광대옥미수립수적영향규률，채용인공차광모의약광협박，설치추웅시기화토사기지속10 d 60%화90%량개불동차광강도적약광처리，연구료화기약광대자수소화수정、결실，간물질적루급기향자수분배적영향。결과발현，화기약광협박도치옥미지상부총간물질일증중량강저，간물질분배도자수적비례감소，자수생장변만，수정결실솔강저，영향정도수차광솔적증가이증대。추웅시기60%화90%차광처리10 d후회복자연광조결실솔교처리결속시적수정솔균명현제고，토사기60%화90%차광처리10 d후회복자연광조결실솔교처리결속시적수정솔강저화지평。추웅시기광조불족도치수립수교대조하강57%~91%；토사시기광조불족도치수립수교대조하강43%~81%。무론대우추웅시기환시토사기，차광처리기간적일평균광합유효복사강도재수립형성중작용최대，기차위처리기간적지상부총간물질일증중。대우토사기，처리기간적일평균온도대수립수야구유직접적정효응。
In order to explicit the effect of low light at flowering stage on the kernel number per ear of maize,we simulated low light stress through artificial shading,conducted two shading rate(60%,90%)treatments for continuous 10 days at initial tasseling stage and at silking stage,and studied the effects of low light at flowering stage on the fertilization and seed setting of florets on fe-male ears,as well as the accumulation of dry matter and its distribution to female ears. It was found that low light stress at flowering stage led to the decrease in daily weight gain of aboveground total dry matter,the reduction in distribution proportion of dry matter to female ears,the slowing of female ear growth,and the decline in rate of fertilization and seed setting;the influence of low light en-larged when the shading rate increased. Compared with the floret fertilization rate at the end of both 60% and 90% shading rate treatments at initial tasseling stage,the final seed setting rate was markedly increased. While in comparison with the floret fertiliza-tion rate at the end of both 60% and 90% shading rate treatments at silking stage,the final seed setting rate was decreased or simi-lar. The final kernel number per ear of maize was decreased by 57% ~91% and 43% ~81% due to the light insufficient at initial tasseling stage and at silking stage,respectively. The daily average photosynthetically active radiation intensity in shading treatment period of both initial tasseling stage and silking stage had the greatest effect on the formation of kernels,followed by daily weight gain of aboveground total dry matter in shading treatment period. The daily average temperature in shading treatment period of silking stage also had directly positive effect on the kernel number per ear of maize.
