株行配置对带状条播小麦群体光环境及抗倒伏性能的影响

【目的】旨在筛选四川丘陵带状机播小麦高产抗倒的株行配置方式。【方法】采用二因素裂区设计，主区为品种，选用紧凑型川农27和半紧凑型绵麦367，副区为带宽2 m和种植密度150×104 hm-2固定情况下的7种行数和行距配置方式，即每带种植5行和行距20 cm + 20 cm + 20 cm + 20 cm（CK，传统“双三零”模式）、每带3行和行距30 cm + 30 cm（F3-1）、每带3行和行距35 cm + 35 cm（F3-2）、每带3行和行距40 cm + 40 cm（F3-3）、每带4行和行距20 cm + 20 cm + 20 cm（F4-1）、每带4行和行距20 cm + 30 cm + 20 cm（F4-2）以及每带4行和行距20 cm + 40 cm + 20 cm（F4-3），研究减少种植行数和扩大行距对带状条播小麦群体透光率、抗倒伏性能及产量的影响，并探讨了透光率与抗倒伏性能间的关系。【结果】两品种表现一致，带状小麦边行抗倒伏性能显著高于内行，内行抗倒伏性能与群体透光率呈显著正相关。种植行数由5行减少为3或4行，再增大行距后，群体透光率显著提高，边行与内行的抗倒伏性能均得到改善，内行优化效果尤为显著，表现为株高和重心高度降低，单茎干物质积累量增多，基部第二节间缩短变粗，茎壁加厚，机械强度、节间充实度、节间干密度、纤维素及木质素含量提高，倒伏指数减小，边行优势减弱，群体更为均衡，田间不易发生倒伏，且成穗数及产量增加。CK的边行茎秆质量最优，抗倒伏能力最强，但内部透光率最低，内行茎秆质量严重劣化，以中间行最为显著，边行优势最强，田间倒伏率高，且产量低于F3-3和F4-3，仅与F3-2和F4-2相当。【结论】四川丘区带状机播小麦高产抗倒最佳株行配置方式为种植3行行距40 cm+40 cm或种植4行行距20 cm+40 cm+20 cm，其次为种植3行行距35 cm+35 cm或种植4行行距20 cm+30 cm+20 cm，以上均可替代传统“双三零”模式。

Effects of Plant and Row Allocation on Population Light Environment and Lodging Resistance of Strip Sown Wheat in Drill

【Objective】 The objective of this study was to screen an optimum plant and row space allocation pattern for mechanical strip sown wheat with high yield and lodging resistance in hilly regions of Sichuan.【Method】Two-factor split-plot design was applied in an experiment. The main-plot was two plant-type wheat cultivars, Chuannong 27 of compact-short and Mianmai 367 of intermediate type, and the sub-plot was seven plant and row allocation patterns with different numbers of rows and row spacing under 2 m wide strip type and 150×104 hm-2 planting density unchanged condition. The traditional double-three-zero strip planting pattern, planting five rows with row spacing of 20 cm+20 cm+20 cm+20 cm in a strip, as the CK. F3-1, F3-2 and F3-3 indicated planting three rows with row spacing of 30 cm+30 cm, 35 cm+35 cm and 40 cm+40 cm, respectively. F4-1, F4-2 and F4-3 indicated planting four rows with row spacing of 20 cm+20 cm+20 cm, 20 cm+30 cm+20 cm and 20 cm+40 cm+20 cm in a strip, respectively. The effects of reducing the number of planting rows and widening row spacing on light transmission rate, lodging resistance and yield were investigated, and the correlation of light transmission rate with lodging resistance was analyzed.【Result】Two wheat cultivars demonstrated consistently. Lodging resistance of edge row was significantly higher than that of inner row, and lodging resistance of inner row was positively correlated with light transmission rate. After reducing the number of planting rows from 5 to 4 or 3 and widening row spacing, light transmission rate was significantly improved, and lodging-resistance of edge row and inner row were enhanced, too, especial for the inner row. The related lodging resistance index of inner row indicated that plant height and height of gravity centre decreased, and the second basal culm internode became shorter and thicker, meanwhile, dry weight per stem, wall-thickness, mechanical strength, culm dry density, culm filling degree, the cellulose and lignin content increased, while lodging index decreased. Furthermore, the border advantage was cut down, and the expression of lodging resistance showed well in field test. Besides, spike number and yield increased. The edge row of CK had the best culm quality and the strongest lodging resistance, but the light transmission rate was the lowest, and culm quality of inner row showed serious deterioration, especial for the middle row. What’s more, CK demonstrated the strongest border advantage and the highest lodging odds in field test. In addition, the yield of CK was lower than that of F3-3 and F4-3, and was equivalent to that of F3-2 and F4-2.【Conclusion】Therefore, the allocation pattern, planting three rows with row spacing of 40 cm+40 cm or planting four rows with row spacing of 20 cm+40 cm+20 cm in a strip, is the optimum plant and row allocation pattern for mechanical sowing strip wheat with high yield and lodging resistance in hilly regions of Sichuan, and the allocation pattern, planting three rows with row spacing of 35 cm+35 cm or planting four rows with row spacing of 20 cm+30 cm+20 cm in a strip, is the second. On the whole, the above four patterns can replace the traditional double-three-zero strip planting pattern.