稻虾共作与栽插密度对优良食味粳稻物质生产及其产量的影响

Effects of rice-shrimp co-cultivation and density on material production and yield of good eating quality japonica rice

以常规种植模式为对照,研究稻虾共作和不同机插密度对南粳9108、南粳57182个优良食味粳稻品种物质生产及其产量的影响。结果表明:与常规种植相比,稻虾共作模式各密度下水稻前期生长慢,茎蘖数减少,后期叶面积指数衰减慢,群体生长率高,叶片光和特性较好,每穗粒数和千粒重提高,有效穗和结实率降低,总干物质积累量和茎叶物质转运量减少,最终产量显著低于常规种植模式,南粳5718减少2.06 t·hm^(-2),南粳9108减少1.18 t·hm^(-2);机插密度对水稻生长发育的影响主要表现为叶面积指数和干物质积累随密度的降低而减少,群体生长率、后期干物质积累量、剑叶SPAD值和净光合速率随密度的降低而增加,有效穗数受到显著影响,每穗粒数和结实率随密度的提高而减少,不同种植模式下水稻产量均以株距12 cm为最高。稻虾共作模式下2个品种各有优缺点,应根据品种特点搭配不同栽培技术,其中肥料和密度最关键。

Compared with conventional cultivation, the effects of rice-shrimp co-cultivation and different machine-planting densities on the biomass production and yield of two good eating quality japonica rice varieties, Nanjing 9108 and Nanjing 5718, were studied. The results showed that compared with conventional cultivation, the growth of rice in the early stage was slow, the number of stems and tillers decreased, the leaf area index in the later stage decayed slowly, the population growth rate was high, and the leaf light and characteristics were better in rice-shrimp co-cultivation. The effective panicle and seed setting rate decreased, the total dry matter accumulation and the stem and leaf material transport decreased, and the final yield was significantly lower than that in the conventional planting mode, Nanjing 5718 decreased by 2.06 t·hm^(-2), Nanjing 9108 decreased by 1.18 t·hm^(-2);The leaf area index and dry matter accumulation decreased with decreasing density, and the population growth rate, late dry matter accumulation, flag leaf SPAD value and net photosynthetic rate increased with decreasing density, which significantly affected the effective panicle number. The number of grains per panicle and seed setting rate decreased with the increase of density. The yields of different planting patterns and different varieties were the highest when the plant spacing was 12 cm. The two varieties had their own advantages and disadvantages in the model of rice-shrimp co-cultivation. The adoption of cultivation techniques, especially fertilization and spgcing, should be based on the characters of the rice varieties used in rice-shrimp co-cropping system.