气象因素对玉米果穗建成影响

Effects of Dry Matter Accumulation and Meteorological Factors on Maize Ear Establishments

通过大田不同播期试验,研究播期气象因素差异对不同品种玉米果穗建成的影响。结果表明,双穗率对穗数具有显著的间接负效应,空秆率对穗数具有显著的直接负效应,果穗分蘖率是影响空秆率的重要因素。播期对果穗建成因素的影响均达显著或极显著水平,品种间穗数无差异,但双穗率和空秆率差异显著。出苗至拔节期日温差越高和适当降雨,双穗率和空秆率越低,穗数越多;出苗至拔节期和拔节至大喇叭口期内高温危害,以及拔节至吐丝期夜温升高、日温差变小和渍涝胁迫,均显著提高双穗率和空秆率;吐丝后14 d内高温天数导致花丝受精率降低或者受精花丝子粒败育,降低穗数。通过调整播期调控玉米果穗建成期气象因素是构建高产多穗群体的技术手段之一。

A field experiment using three maize hybrid was conducted by 10 sowing date（SD） to study the ef-fects of different meteorological factors response to SD, on maize ear establishments. The results showed that doubleear rate（DER） had significantly negative indirect effects on ear number（EN）, while bare plant rate（BPR） which waseffected by ear tiller rate was significantly and negatively direct affected on EN. EN, BER and BPR were significant-ly different by SD delayed, meanwhile EN had no significantly different belong to maize hybrids, however, differenthybrids abstained significantly different DER and BPR. The higher mean diurnal temperature range（M△T） and opti-mized precipitation during VE-V6 interval reduced DER and BPR, and increased EN. DER and BPR were signifi-cantly increased due to the higher maximum temperature during VE-V6 and V6-V12, the minimum temperature in-creasing, M△T decreasing, and flooding stress with higher precipitation during V6-V12 and V12-R1 interval. Thedays of maximum temperature higher than 34℃ in 14 d after silking may lead lower fertilization rate or kernels abor-tion, increased BPR and decreased EN. So, adjust sowing date to obtain the optimized meteorological condition formaize ear formation is one of the cultivation techniques to grain higher yield by more ear number.