中国苜蓿、黑麦草和燕麦草产量差及影响因素

【目的】在国家大力推进“粮转饲”和种植业结构调改的背景下，研究苜蓿、黑麦草和燕麦草3种栽培牧草产量差及影响因素，为揭示牧草生产潜力和制定牧草高产高效措施提供科学依据。【方法】从中国知网和Web of Science两个数据库，以“苜蓿产量 施肥”、“黑麦草产量 施肥”、“燕麦草产量 施肥”、“牧草栽培技术”、“Alfalfa, Fertilizer, China”、“Alfalfa, Irrigation, China”为关键词，共收集目标文献176篇，其中关于中国苜蓿的文章101篇、黑麦草的文章51篇和燕麦的文章24篇。总结中国苜蓿、黑麦草和燕麦草的产量潜力和产量差。通过分析施肥、播种和灌溉对牧草产量的影响，阐明影响牧草产量差的因素及消减途径。【结果】当前中国栽培苜蓿、黑麦草和燕麦草的产量潜力分别为24、26和22 t·hm^-2，农户产量分别实现了产量潜力的28%、63%和41%。氮磷肥的施用、播种和灌溉可以显著地影响牧草产量，苜蓿的产量最佳施肥量约为氮肥(N)52 kg·hm^-2，磷肥(P₂O₅)141 kg·hm^-2，最佳播种量约为20 kg·hm^-2，最佳灌水量约为5 737 m³·hm^-2；黑麦草的产量最佳施肥量约为氮肥(N)585 kg·hm^-2，磷肥(P₂O₅)46 kg·hm^-2，最佳播种量约为30 kg·hm^-2；燕麦草的产量最佳施氮量尚没有明确的结果，在施氮量＜225 kg·hm^-2时，燕麦草的产量随施氮量的增加呈线性的增加，其产量最佳施磷(P₂O₅)量约为128 kg·hm^-2，最佳播种量约为180 kg·hm^-2。【结论】中国栽培苜蓿、黑麦草和燕麦草有很大的增产空间，增产潜力分别为17、10和13 t·hm^-2。合理的施肥、播种和灌溉可以缩小产量差，优化施肥量可以使苜蓿增产约3.4 t·hm^-2，黑麦草增产约1.5 t·hm^-2，燕麦草增产约4.2 t·hm^-2。优化播种量可以使苜蓿增产60%，燕麦草增产78%，但是仅通过优化播种量并不能使黑麦草增产。优化灌溉量可以使苜蓿增产约9.1 t·hm^-2。

Yield Gap of Alfalfa,Ryegrass and Oat Grass and Their Influence Factors in China

【Objective】 Under the background of turning crop to forage and adjustment of plantation structure, the study on yield gap of alfalfa, ryegrass and oat grass is crucial for revealing yield potential. It can also provide a scientific basis for making high yield and high efficiency forage management strategies. 【Method】 The publications were collected by searching China National Knowledge Infrastructure and Web of Science with the keywords of “Alfalfa yield, Fertilizer”, “Ryegrass yield, Fertilizer”, “Oat grass yield, Fertilizer”, “Forage planting technology”, “Alfalfa, Fertilizer, China”, “Alfalfa, Irrigation, China”. A total of 176 published literatures were collected, including 101 articles for alfalfa, 51 articles for ryegrass and 24 articles for oat grass. This study summarized the yield potential and yield gap for three major cultivated forage species in China. Meta-analysis method was implied to quantify the effect of fertilization, sowing rate and irrigation rate on yield of three main cultivated forage species. This paper made a preliminary illustration about the factors that affect yield gap and ways to close the yield gap. 【Result】 The yield potential was 24 t·hm^-2 for alfalfa, 26 t·hm^-2 for ryegrass and 22 t·hm^-2 for oat grass. The farmer’s average yield of alfalfa, ryegrass and oat grass was 28%, 63% and 41%, respectively, of the yield potential. The fertilizer application rate of nitrogen (N) and phosphorus (P₂O₅), sowing rate and irrigation rate significantly affected forage yield. The optimized N and P₂O₅ application rate was 52 and 141 kg·hm^-2 for alfalfa, 585 and 46 kg·hm^-2 for ryegrass. For oat grass, the optimal nitrogen fertilizer application rate was not clear, but within the total amount of 225 kg·hm^-2, oat grass yield increased linearly with the increasing of N application rate. The optimal P₂O₅ application rate was 128 kg·hm^-2 for oat grass. The optimized sowing rate was 20 kg·hm^-2 for alfalfa, 30 kg·hm^-2 for ryegrass and 180 kg·hm^-2 for oat grass. The optimized irrigation volume was 5 737 m³·hm^-2 for alfalfa.【Conclusion】There was still a huge potential to increase yield of alfalfa, ryegrass and oat grass. The yield gap of alfalfa, ryegrass and oat grass was 17, 10 and 13 t·hm^-2. Furthermore, reasonable fertilizer application rate, seeding rate and irrigation volume are important to cut yield gap. By optimizing the fertilizer application rate, the yield of alfalfa, ryegrass and oat grass could increase by 3.4, 1.5 and 4.2 t·hm^-2. Suitable sowing rate could increase the yield by 60% for alfalfa, 78% for oat grass, but it was not enough to improve the yield of ryegrass only by adjusting the sowing rate. Optimal irrigation volume could increase the alfalfa yield by 9.1 t·hm^-2.