不同机械直播方式对水稻分蘖特性及产量的影响

为研究不同机械直播方式对水稻分蘖特性的影响,以常规稻常农粳7号、超级稻南粳44与杂交粳稻甬优2638、甬优7号为材料,在江苏稻麦两熟制条件下研究了水(湿润)点播和条播2种机械直播方式水稻分蘖发生和成穗特性及其对群体产量的贡献。结果表明,不同直播方式对水稻分蘖发生与成穗特性有显著影响。点播和条播方式一次分蘖发生叶位均为5个,即主茎第1叶位到第5叶位;二次分蘖发生叶位以主茎第1分蘖的第1、2叶位和主茎第2分蘖的第1叶位为主。一次分蘖发生率点播方式低于条播方式,主茎第3、4叶位分蘖发生率为100%;二次分蘖发生率点播方式高于条播方式。4个品种均未见三次及三次以上分蘖发生。点播方式产量显著高于条播方式(p0.05),且不同直播方式对水稻茎蘖成穗与高产利用存在差异(p0.05)。一次分蘖的第1~5叶位是可成穗叶位,以第1~3叶位成穗为主,成穗率50%以上,条播方式成穗率高于点播方式。主茎第1分蘖的第1叶位和主茎第2分蘖的第1叶位是二次分蘖成穗的主要叶位,但成穗率较低;点播方式成穗率低于条播方式,不同品种间存在差异。一次分蘖穗对产量贡献率在不同蘖位间存在显著差异(p0.05),主茎第3分蘖生产力最高,对产量的贡献率最高,其中点播方式大于条播方式。二次分蘖穗对产量贡献率较小,点播方式高于条播方式。进一步对分蘖的穗粒构成分析表明,主茎第3分蘖穗单位面积穗数和每穗粒数较高,每穗粒数表现为主茎第3分蘖穗点播方式高于条播方式。该文明确了不同机械直播方式水稻分蘖成穗规律,为直播稻大面积高产提供了技术依据。

Effect of different mechanical direct seeding methods on tiller characteristics and yield of rice

Abstract: Little information is available on tillering characteristics and their relationships with high yield in the different patterns of water mechanical-direct-seeding cultivation in rice have not been understood. The experiments were conducted using four varieties, conventional rice Changnongjing 7, super rice Nanjing 44, hybrid rice Yongyou 2638, and Yongyou7, to investigate the characteristics of tillers emergence and panicle formation and its productivity and contribution to yield by the two mechanical-direct-seeded planting patterns - hole seeding and seeding in drill cultivation. The results indicated that the tillers emergence and the panicle rates were significantly affected by the different mechanical-direct-seeding patterns. In the two planting patterns, the leaf position number of tillers emergence in the main stem were five, namely leaf 1/0 to leaf 5/0 and secondary tillers group emerged mainly in 1/1, 2/1, and 1/2 with the difference in four varieties. The percentage of primary tillers emergence of different leaf positions in hole seeding pattern was lower than that of seeding in drill pattern, but was higher than the percentage of secondary tillers emergence. The percentage of primary tillers emergence in 3/0 and 4/0 was 100%. Tertiary tillers and even more grades tillers did not initiate in the two planting patterns. The grain yield of all four rice varieties under the hole seeding pattern was higher than that of the seeding in drill pattern (p<0.05), and the different planting patterns affected the earbearing percentage of tillers and their contribution to high yield (p<0.05). The tillers of 1/0 to 5/0 in the main stem were able to earbear, among them 1/0 to 3/0 were main leaf positions with higher percentage of panicle formation (more than 50%), and the percentage of panicle formation of the hole seeding cultivation was higher than that of the seeding in drill cultivation. The main leaf positions of panicle formation of secondary tillers were 1/1 and 1/2 with a very low earbearing percentage, and earbearing percentage of the hole seeding pattern was lower than that of the seeding in drill pattern. The percentage of yield of primary tillers group contribution to total population yield was significant in different tillers (p<0.05) and the tiller 3/0 had maximum productivity and contributive proportion, and the contributive proportion of tillers in the hole seeding pattern was higher than that of the seeding in drill pattern. But the contributive proportion of the secondary tillers was lower with the trend of the hole seeding pattern higher. By analysis of characteristics of panicles and spikelets, in tiller 3/0 the panicles number per area and spikelets number per panicle were bigger, and the hole seeding pattern had bigger spikelets number per panicle than the seeding in drill pattern. The appropriate production application and available regulation approach of the different patterns of water mechanical-direct-seeding cultivation in rice, such as management measures of manure and water, etc., are also discussed in the present paper. The experiment indicates the rules of tillers emergence and panicles formation for rice in water mechanical-direct-seeding cultivation, which provides a theoretical basis for high yield of the farm equipment in field production.