岷县不同茬口对当归苗栽生长及抗病性的影响

Effect of various crop residues on growth and disease resistance of Angelica sinensis seedlings in Min County

当归传统育苗方式造成严重的荒坡地水土流失。在当归道地产区甘肃省岷县通过定向种植小麦、黄芪、马铃薯和当归培育作物茬口基础上,再行当归育苗,育苗期测定苗栽生长动态,育苗结束测定苗栽质量性状及抗病性指标,利用主成分分析确定各指标权重,再结合隶属函数法综合评判,旨在揭示作物茬口对当归苗栽生长发育和抗病性的影响,为筛选适宜当归育苗的农茬口土壤资源提供科学依据和技术参考。结果表明,各茬口条件下当归出苗数和幼苗地上部分生长指标均表现显著差异,小麦茬和黄芪茬当归成苗数和地上生长指标均维持在较高水平,根系发达,生长势强,个体质量优异,根病发病率和病情指数均低,而马铃薯茬和当归重茬苗栽受季节影响较大,随生长期延后当归死苗率提高,易形成老小苗,发病率高达36.7%以上。综合指数大小依次为黄芪茬(0.7840)>小麦茬(0.7816)>当归重茬(0.4731)>马铃薯茬(0.1656)。马铃薯茬死苗率最高,当归重茬根腐病最为严重,说明岷县正茬黄芪和小麦茬口是适宜当归熟地育苗的优异床土资源。

Traditional seedling nursery methods relying on uncultivated land for Angelica sinensis have caused serious soil erosion and debris flow.A study has been undertaken to explore the use of crop stubble land for the production of A.sinensis seedlings.Using the stubble fields of Triticum aestivum,Astragalus membranaceus,Solanum tuberosum and A.sinensis crops in Min county of Gansu province,seedlings were cultivated and their growth and resistance indicators measured.Index weights were calculated using principle component analysis and the membership function method was also used to explore the effect of crop stubbles on the seedling nursery.Results showed that the aboveground growth of seedlings varied significantly with different crop stubbles.Seedlings cultured in wheat and Astragalus residues showed the strongest growth indicators,with strong roots and growth power resulting in excellent individual plant quality with a low root incidence rate and disease index.Seedlings produced under potato and Angelica residues were highly affected by seasonal variations,resulting in high death rates and elongation of the growth period.The oldest and smallest seedlings occurred in the continuous cropping system and the potato residue,which had over 36.7%disease rates.According to the comprehensive index,the residues were ranked as Astragalus(0.7840)>wheat(0.7816)>Angelica(0.4731)>potato(0.1656).Seedlings produced in potato residue showed the highest death rate and seedlings in Angelica residue exhibited the highest incidence rate.These results suggest that the residues of wheat and Astragalus crops provide the most suitable soil resources for cultivating Angelica seedlings in Min county.