Suitable mechanical transplanting spacing promoting rice growth and increasing rice yield

Abstract: In mechanical rice transplanting, hill-row spacing combination directly influenced the growth and yield of rice. To compare the effect of hill-row spacing on mechanical transplanting rice, the growth and yield of rice, we set up 2-year field experiments located in Zhangjiagang, Jingjiang and the Yellow Sea farm in Jiangsu Province, separately. The rice breed planted in Zhangjiagang, Jingjiang and the Yellow Sea farm was Wuyunjing 29, Wuyunjing24 and Lianjing 7, separately, all of which were japonica hybrid rice. There were 3 row-hill spacing treatments in-at each site, which the row spacing by hill spacing was 30 cm by 11 cm, 25 cm by 14 cm, 25 cm by 11 cm, each repeated 3 times. By the influence of the spacing, the area of 30 cm by 11 cm (row spacing by hill spacing), 25 cm by 14 cm (row spacing by hill spacing) and 25 cm by 11 cm (row spacing by hill spacing) was 135 m2, 150 m2 and 150 m2, separately. At the same site within each treatment, only the row-hill spacing differences were the mutation factors, the other factors were controlled. The effect of the mechanical transplanting rice, the tillering dynamics of rice, yield and yield composition of rice were tested. The effect of mechanical rice transplanting measured immediately after transplanting. 200 continuous points were taken in each area; the number of plants per hole, seedling injury and inverted were recorded to calculate the average number of plants per hole, drain planting rate, seedling injury rate and seedling inverted rate. To determine the tillering dynamic, the number of tillers was counted every 7 days from rice transplanting to the full panicle stage, 20 points for each plot were fixed. Actual yield of rice was determined after ripening. For each treatment, 3 m2 of rice were weighed after harvesting to calculate the actual yield, repeated 3 times. According to the average number of plants per hill, 3 hill plants were selected for testing, and then the yield component and the theoretical yield of rice were calculated. SPSS17.0 and Excel 2007 were used for the statistical analysis. The results are indicated below: 1) Drain planting rate of 25 cm by 14 cm (row spacing by hill spacing) was the lowest, then was 25 cm by 11 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the highest. These indicate that narrow row spacing large hill spacing was conducive to reducing the drain planting rate of rice. No rule was found from the rates of seedling injury and inverted in between these 3 breeds. 2) The number of tillers after tiller stabilization of 30 cm by 11 cm (row spacing by hill spacing) was the highest, and then was 25 cm by 14 cm (row spacing by hill spacing), 25 cm by 11 cm (row spacing by hill spacing) was the lowest. These indicate that large row spacing and hill spacing is conducive to the promotion of rice tillering. 3) In the aspect of the yield components, ears of 25 cm by 11 cm (row spacing by hill spacing) were the highest, and then were 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. No rule was found between the grain numbers per spike, the seed rate and 1000-grain weight. Finally in the aspect of the theoretical rice yield and the actual rice yield, 25 cm by 11 cm(row spacing by hill spacing) was the highest, and then 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. The theoretical rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 9.68%-26.5% higher than 30 cm by 11 cm (row spacing by hill spacing), and the actual rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 3.18%-20.6% higher than 30 cm by 11 cm (row spacing by hill spacing). The 25 cm by 11 cm (row spacing by hill spacing) row transplanter should be more suitable for mechanical rice planting in Jiangsu Province.