草木犀翻压时期和化肥用量对烤烟生长和产量的影响

魏媛 常春丽 李金秋 王盼盼 贺国强 敖红 王晶英

摘 要：为明确植烟区草木犀用作绿肥的最适翻压时期和烤烟适宜化肥用量，通过田间试验研究了草木犀在3个时期（营养生长期、初花期、盛花期）翻压以及配合化肥的3个用量（不施肥、70%常量施肥和常量施肥）对烤烟生长和产量的影响。结果表明，同一化肥用量下，随着翻压时期的推迟，烤烟的净光合速率、蒸腾速率和叶片羧化效率均显著提高，胞间二氧化碳浓度显著降低;烤烟的经济性状提高，以盛花期翻压最优，盛花期翻压处理的上中等烟比例、产量和产值分别较营养生长期翻压的显著提高18.09%、20.00%和36.29%。同一时期翻压，随着配施化肥用量的增加，光合特性及烤后烟叶的经济性状先增加后降低，均在70%常量施肥量达最大值。可见，草木犀翻压时期的推迟配合化肥用量的适当减施可提高烤烟的光合作用强度，促进干物质的积累，增值提产效果明显，以盛花期翻压配70%常量化肥为宜。

关键词：烤烟;绿肥;草木犀;翻压;化肥用量

Abstract： In order to clarify the most suitable period of Melilotus officinalis （L.） Pall ploughing as a green manure in tobacco-growing areas and the appropriate amount of chemical fertilizers for flue-cured tobacco， field experiments were conducted to study the effects of Melilotus officinalis （L.） Pall at three stages （vegetative growth period， initial flowering period， and full flowering period） and combined with chemical fertilizers. The effects of three dosages （no fertilization， 70% constant fertilization and constant fertilization） on the growth and yield of flue-cured tobacco were analyzed. The results showed that： under the same fertilizer dosage， with the delay of the ploughing period， the net photosynthetic rate， transpiration rate and leaf carboxylation efficiency of flue-cured tobacco were significantly increased and the intercellular carbon dioxide concentration was significantly decreased. The full flowering stage was the best， with the proportion of upper medium tobacco， yield and output value at the full flowering stage significantly increased by 18.09%， 20.00% and 36.29% respectively compared with the vegetative growth period. During the same period of ploughing， with the increase of fertilizer dosage， the photosynthetic characteristics and economic traits of flue-cured tobacco increased first and then decreased， all reached the maximum value of constant fertilizer application at 70%. It can be seen that on the basis of ploughing Melilotus officinalis （L.） Pall， the photosynthetic intensity of flue-cured tobacco could be improved by delaying the ploughing period and reducing the amount of chemical fertilizer， promoting the accumulation of dry matter， with obvious value-adding effects. It was suggested that 70% constant （30% reduction） of chemical fertilizer application rate should be adopted at the full flowering stage.

Keywords： flue-cured tobacco; green manure; Melilotus officinalis （L.） Pall; ploughing; fertilizer consumption

近年來，化学肥料的过量使用导致土壤板结化，透水透气性差，有机质含量下降[1-2]，烟苗对肥料的有效利用率降低，田间生长状态不佳，烤后烟叶的品质和产量下降[3-5]。绿肥是一种含养分完全的生物有机肥源[6]，已有大量研究表明在连作烟田冬季闲置时间种植并翻压绿肥不但能减轻连作障碍，而且能提升土壤有机质含量，起到疏松土壤、活化和富集土壤中速效养分[7-9]、改善烟叶外观和评吸质量、增加土壤微生物和酶活性[10-11]的作用。……