钵苗机插密度对双季晚稻产量及群体质量的影响

以杂交籼稻品种五丰优T025、籼粳杂交稻品种甬优538、常规粳稻品种小叶迟熟为材料,设置5个钵苗机插密度(D1,33 cm×12 cm;D2,33 cm×13 cm;D3,33 cm×14 cm;D4,33 cm×15 cm;D5,33 cm×16 cm),以毯苗机插为对照(CK,30.0 cm×13.2 cm),比较研究了不同钵苗机插密度对双季晚稻产量及群体质量的影响,旨在探明水稻钵苗机插在双季晚稻区的适宜栽插密度。试验结果表明:(1)三种类型水稻的产量均随移栽密度的增加而增加,相同密度条件下D1处理产量均极显著高于CK,2年平均增产8.13%~9.50%;(2)钵苗机插水稻移栽后群体的茎蘖数均表现为处理D1D2D3D4D5,与CK相比,D1处理的茎蘖数栽后增长快,拔节后群体茎蘖数消减缓慢,成穗率高;(3)移栽期至拔节期、拔节期至抽穗期、抽穗期至成熟期三种类型水稻钵苗机插的干物质积累量、群体生长率、光合势均表现为处理D1D2D3D4D5,移栽期至拔节期CK的干物质积累量和光合势大于D1处理,拔节期至抽穗期、抽穗期至成熟期D1的干物质积累量、群体生长率及光合势均高于CK;(4)钵苗机插水稻主要生育期的群体干物质量均表现为处理D1D2D3D4D5,而单茎干物质量却表现出相反的趋势;(5)钵苗机插水稻在主要生育时期的叶面积指数及抽穗期群体的有效叶面积率、高效叶面积率及粒叶比均随密度的增加呈上升趋势,抽穗期群体的有效叶面积率、高效叶面积率及粒叶比D1处理极显著高于CK。本试验结果表明,在双季晚稻区不同类型水稻品种钵苗机插最适宜行株距为33 cm×12 cm。

Effects of Planting Density with Bowl Mechanical-transplanting Method on Yield and Pop-ulation Quality of Double-cropping Late Rice

In order to study the effects of planting density with bowl mechanical-transplanting method on yield and population quality of double-cropping late rice and identify the suitable planting density, a field experiment was conducted using indica hybrid rice Wufengyou T025, indica-japonica hybrid rice Yongyou 538 and conventional japonica rice Xiaoyechishu with five planting densities (D1, 33 cm ×12 cm; D2, 33 cm ×13 cm; D3, 33 cm ×14 cm; D4, 33 cm ×15 cm; D5, 33 cm ×16 cm), and the conventional blanket seedling mechanical-transplanting as control (CK, 30 cm ×13.2 cm). The experimental results were as follows: (1)The yield of the three types of rice increased with the increase of the density, under the same density, the yield of D1 treatment was significantly high-er than that of CK, and the average yield of two years increased by 8.13%~9.50%; (2)The number of stems and tillers of nutrition bowl mechanical-transplanting rice were D1>D2>D3>D4>D5, compared with CK, slower reducing rate of tillers after jointing, higher ratio of productive tillers to total tillers at maturity;(3)Dry matter accumulation, population growth rate and photosynthetic potential of nutrition bowl mechanical-transplanting of three type rice were D1>D2>D3>D4>D5 during transplanting to jointing, jointing to head-ing, heading to maturity, the dry matter accumulation and photosynthetic potential of CK were larger than that of D1 from transplanting to jointing, but the dry matter accumulation, population growth rate and photosynthetic potential of D1 were higher than that of CK from jointing to heading and heading to mature; (4)Dry matter weight of population of nutrition bowl mechanical-transplanting rice during the main growth period showed D1>D2>D3>D4>D5, but the dry matter weight of per stem performed opposite trends;(5)Leaf area index of nutrition bowl mechanical-transplanting rice during the main growth period and the ratio of effective leaf area, ratio of leaf area from flag leaf to 3rd leaf, the ratio of grain to leaf at heading showed a rising trend with the increase of density, the ratio of effective leaf area, ratio of leaf area from flag leaf to 3rd leaf and the ratio of grain to leaf of D1 was significantly higher than that of CK at heading. The results showed that the density of 33 cm ×12 cm with bowl mechanical-transplanting of double-cropping late rice is most appropriate.