不同收获方式对蔗田土壤容重及甘蔗宿根出苗的影响

[目的]研究机械收获对宿根甘蔗出苗及根系生长的影响,为筛选适宜机械收获的甘蔗品种及改进相应栽培技术提供理论依据.[方法]采用双因素裂区设计,设A1（人工收获）、A2（机械收获）为主处理,以B1（ROC22）、B2（桂糖29号）、B3（桂糖33号）3个副处理进行田间试验,通过测定土壤容重、宿根出苗发株和宿根根系生长情况等参数研究机械收获对宿根甘蔗生长的影响.[结果]与人工收获相比,机械收获处理显著增加蔗地土壤容重.与人工收获方式相比,机械收获下,B1和B2的单位面积根数和单位面积根鲜重极显著降低,出苗数显著增加;同品种甘蔗宿根单位面积生物量差异均不显著;B2和B3的根冠比均显著降低,其中B2达极显著水平;B1新根单重极显著降低,其他两个品种新根单重差异均不显著;3个品种单株苗重均显著降低;B2和B3的单株活根数均显著降低.与新植有效茎相比,人工收获处理3个参试品种宿根有效茎数均有所增加,增幅均在10.00％以内,其中B3增幅最高,为9.47％;机械收获处理B1和B2宿根有效茎数增幅分别为12.55％和18.08％,B3宿根有效茎数降低13.26％.[结论]甘蔗机械收获后,行沟间土壤容重明显增加,对甘蔗根系的生长产生限制作用,不同品种耐机械碾压能力不同,桂糖29号综合表现较好.

Effects of different harvesting methods on soil bulk density and seedling roots of ratoon sugarcane

[Objective]This experiment was conducted to study the effects of different harvesting methods on soil bulk density and seedling roots of ratoon sugarcane in order to select the suitable cultivars and improve cultivation technology of mechanical harvesting.[Method]The split plot design with two factors was used setting the main treatments of A1 （artificial harvesting）,A2 （mechanical harvesting）,and the deputy treatments of B1（ROC22）,B2（GT29）and B3 （GT33）.The effects of mechanical harvesting on the growth of ratoon sugarcane were evaluated by soil bulk density,seedling and root growth parameters of ratoon sugarcane.[Result] Compared with artificial harvesting,mechanical harvesting significantly increased the soil bulk density.The root number and fresh root weight per unit area of B1 and B2 reduced significantly,however seedling number increased significantly.The biomass difference was not significant for the same cultivar.The root shoot ratio of B2 and B3 reduced significantly,and B2 reached the extremely significant level.The live root number of B1 reduced significantly,but the difference was not significant between the other two varieties.The seedling weight of all varieties reduced significantly.The live root number of B2 and B3 also reduced significantly.Compared with the effective stalk number of new-planting sugarcane,the effective stalk number of the three tested varieties harvested artificially rose by 10.00％,and B3 increased most （9.47％）.Regarding mechanical harvesting,the increment of effective stalk number of B1 and B2 was 12.55％ and 18.08％,respectively,however the effective stalk number of B3 was down by 13.26％.[Conclusion]Mechanical harvesting could increase soil bulk density and inhibit the roots development of sugarcane.The tolerance for mechanical harvesting varies among sugarcane cultivars,and the overall performance of Guitang 29 is good.