50份毛叶苕子品种(系)在青海作秋绿肥的能力评价

  【目的】  毛叶苕子是重要的肥饲兼用绿肥作物。分析不同品种毛叶苕子产草量及氮(N)、磷 (P) 、钾 (K) 吸收能力，以期筛选出适宜青海地区绿肥栽培的品种 (系)。  【方法】  在田间条件下，分析了50份毛叶苕子品种 (系) 分枝期和初花期地上部生物量和N、P、K累积量，及土壤速效养分含量变化。运用主成分分析和聚类分析评价不同毛叶苕子N、P、K吸收能力。  【结果】  供试毛叶苕子初花期鲜草产量及N、P、K累积量分别为18.35～46.94 t/hm2、101.51～278.98 kg/hm2、10.39～29.80 kg/hm2和59.33～157.54 kg/hm2。毛荚野苕子初花期鲜草产量最高，比当地主栽品种青苕1号提高了61.47%。78-14品系N、P、K累积量均最高，比青苕1号分别提高了92.81%、67.51%和86.50%。分枝期和初花期鲜重、干重和N、P、K累积量以及鲜重增长量和干重增长量的主成分分析显示排名前5的资源分别为78-14、苕藤选、毛荚野苕子、山东早熟苕和78-171苕子，78-14得分最高 (4.85)，苏联苕子得分最低 (?5.06)。聚类分析结果显示，N、P、K吸收能力可聚为强、较强、中等、一般4类。N素吸收能力强、较强、中等、一般的分别有1、12、15、22份资源。P素吸收能力强、较强、中等、一般的分别有4、24、6、16份资源。K素吸收能力强、较强、中等、一般的分别有4、12、19、15份资源。N、P、K吸收能力最强的资源平均吸收量分别达到278.98、27.94和145.91 kg/hm2。与播前比，种植毛叶苕子降低分枝期和初花期土壤无机氮、有效磷和速效钾含量，能够充分利用休闲期土壤养分。  【结论】  在青海农田中，不同品种(系)毛叶苕子在生物量和养分吸收能力方面表现出较大差异，综合来看，品系 78-14 在生物量及N、P、K吸收能力均表现突出，苕藤选、毛荚野苕子表现出较好的P、K吸收能力，可作为青海农区有潜力的绿肥备选资源在生产中验证。

Capability evaluation of 50 hairy vetch cultivars (lines) as autumn green manure in Qinghai Province,Northwest China

  【Objectives】  Hairy vetch (Vicia villosa Roth.) is one of China’s most important fertilizer and forage dual-purpose green manure crops. The nitrogen (N), phosphorus (P), and potassium (K) accumulation and aboveground biomass of different hairy vetch cultivars (lines) were investigated to select those suitable for green manure cultivation in the Qinghai area.  【Methods】  The N, P, and K accumulation and aboveground biomass of 50 cultivars (lines) and soil nutrients were analyzed under field conditions at the branching and initial flowering stages. Hairy vetch’s N, P, and K absorption capacity were evaluated using principal component and cluster analysis.  【Results】  The range of values recorded for fresh grass yield, N, P, and K accumulation was 18.35–46.94 t/hm2, 101.51–278.98 kg/hm2, 10.39–29.80 kg/hm2, and 59.33–157.54 kg/hm2, respectively, for hairy vetch cultivars at the initial flowering stage. Cultivar ‘Maojiayeshaozi ’ had the highest fresh yield and ‘78-14’ had the highest N, P, and K accumulation capacity. The yield and N, P, and K accumulation in ‘Maojiayeshaozi ’ exceed the main local ‘Qingshao 1’ by 61.47%, 92.81%, 67.51%, and 86.50%, respectively. Principal component analysis showed that the top five cultivars were ‘78-14’, ‘Shaotengxuan’, ‘Maojiayeshaozi’, ‘Shandongzaoshushao’, and ‘78-171 shaozi’. Moreover, ‘78-14’ had the highest score (4.85) while ‘Soviet Union shaozi’ had the lowest score (?5.06). Cluster analysis showed that the absorption capacity of N, P, and K clustered into four groups in each case. For N, the high, higher, medium, and general absorption capacities were recorded for 1 cultivar, 12 cultivars, 15 cultivars, and 22 cultivars. For P, the high, higher, medium, and general absorption capacities were observed for 4 cultivars, 24 cultivars, 6 cultivars, and 16 cultivars. For K, the high, higher, medium, and general absorption capacities were recorded for 4 cultivars, 12 cultivars, 19 cultivars, and 15 cultivars. The group with high N, P, and K absorption capacities recorded 278.98, 27.94, and 145.91 kg/hm2, respectively. Compared with pre-sowing, planting hairy vetch decreased inorganic N, available P and K contents at the branching and initial flowering stages, enhancing nutrient utilization in the fallow season.   【Conclusions】  The biomass and nutrient absorption capacity of different hairy vetch cultivars (lines) in Qinghai are different. Overall, ‘78-14’ showed higher N, P, and K absorption capacity, and ‘Shaotengxuan’ and ‘Maojiayeshaozi’ shows higher P and K absorption capacity. Therefore, these cultivars are proposed as potential candidate cultivars for further field evaluation in Qinghai.