不同水直播方式水稻植株抗倒特性研究

Lodging Resistance of Rice under the Different Pattern of Water Direct-seeding Cultivation Method

为研究不同水直播方式水稻植株倒伏的差异,在稻麦两熟制下,以2个常规粳稻(常农粳7号、超级稻南粳44)和2个杂交粳稻品种(甬优2638、甬优7号)为试材,设置水直播点播和条播2种方式,于齐穗后30 d,研究了不同直播方式高产水稻植株地上部分各节间抗倒伏能力的差异,并对倒伏指数、抗折力与茎秆主要物理性状进行相关分析。结果表明,条播方式水稻倒伏比例较大,水稻植株基部第2,3节间抗折力和弯曲力矩,点播方式显著高于条播方式;条播方式倒伏指数显著较高。点播方式水稻株高、重心高度高于条播方式,但相对重心高度低于条播方式。点播方式水稻基部第1,2节间长度显著小于条播方式,基部3个节间的茎秆内径长均显著高于条播方式,除基部第1节间外,基部第2,3节间外径长和茎壁厚度点播方式显著高于条播方式。点播方式基部第1,2节间单位节间干质量显著高于条播方式。上述茎秆性状在不同类型品种间有较大差异。直播水稻茎秆的抗折力和倒伏指数与水稻茎秆基部节间长、茎壁厚、节间充实度等性状密切相关。点播方式水稻具有基部节间短而粗、茎壁较厚,且充实度好的特点,是其抗倒伏能力强的直接原因。

In recent years,cultivation area of direct-seeding rice in Jiangsu Province and nearby regions has been expanding rapidly,the stronger lodging resistance of culm is the key aspect to high yield and excellent-qualities,but the specific research on the influencing factors of lodging resistance is little in direct-seeding rice. At thirty days after heading,a field experiment was conducted with four varieties,conventional rice Changnongjing 7,super rice Nanjing 44,hybrid rice Yongyou 2638 and Yongyou 7,to investigate the differences of rice-stem lodging resistance between two direct-seeding cultivation methods,named hole seeding and seeding in drill cultivation,by measuring the morphological and physical traits of rice basal stems. Furthermore,the correlation analysis between the lodging index,breaking resistance and main culm physical characteristics were studied. The results indicated that the culm lodging resistance of rice planted with different planting methods was significantly different. In field,the lodging rate of hole seeding rice was lower than that of seeding rice in drill. Compared with seeding rice in drill,the breaking resistance of the second basal internode and third basal internode in hole seeding rice was higher,while the lodging index was lower. Plant height and gravity center height in hole seeding rice was longer with the ratio of gravity center height to plant height shorter. In hole seeding rice,length of the first and second basal internode was significantly shorter,culm inside diameter of three internodes from base was longer,and beside the first basal internode,culm outside diameter and culm wall thickness of the second basal internode and third basal internode werelonger,and dry weight of unit internode of the first basal internode and the second basal internode were higher.Those culm physical traits of different type varieties were significantly different. The breaking resistance of the 1st,2nd,3rd basal internode and plant height,gravity center height,culm diameter,culm wall thickness,dry weight of culm,dry weight of unit internode and bending moment had significant or very significant positive correlation,while internodes length showed a significant or very significant negative correlation. The optimal combination of some main culm physical traits of rice was different under different planting methods. The direct reasons for lodging resistance increased in hole seeding rice were short and thick basal internodes,large wall thickness and good culm plumpness status.