喀斯特地区不同核桃品种需冷量分析

Analysis of chilling requirement of different walnut cultivars in karst areas

【目的】研究不同核桃品种的需冷量,为我国南方喀斯物地区发展核桃产业提供参考依据。【方法】以广西河池16个主栽核桃品种为试材,设低温下7个不同需冷量水平,即4℃低温处理400、500、600、700、800、900和1000 h,将包含各品种的混合芽和雄花芽插入装有清水高度约2 cm的瓶子中,放入组织培养室中培养15 d后,统计各核桃品种混合芽和雄花芽萌芽后的长势和生长量,筛选适宜喀斯特地区推广种植的核桃品种。【结果】在16个核桃品种中,张清华的需冷量最低,为600 h;云光山核桃的需冷量次之,为700 h;三台核桃、香玲、大泡、凤优一号、卢逢春、辽核4号和张明卫的需冷量居中,为800 h;娘青和晋龙薄丰的需冷量达900 h;云新、中林1号、元林、美国山核桃和日丽的需冷量均超过1000 h。同一品种核桃雄花的需冷量大于混合芽的需冷量,只有香玲和卢逢春在低温处理900 h后雄花芽的萌芽率达50.0%,其余品种在低温处理1000 h下雄花芽的萌芽率均未达50.0%。在萌芽后的芽长势方面,三台核桃、云新和云光山核桃等品种萌芽后芽的长势较好,中林1号和元林萌芽后长势较差;在芽长总量方面,三台核桃、云新、香玲、云光山核桃、卢逢春、辽核4号、张明卫和晋龙薄丰等品种在1000 h下芽长总量均达到或超过5.00 cm,除卢逢春外,其余7个品种在1000 h处理下芽长总量与其他处理差异显著(P<0.05),中林1号和元林在1000 h下芽长总量为0.50 cm,且中林1号各处理间差异不显著(P>0.05)。【结论】在引种核桃品种时,应尽量选择需冷量要求较低、萌芽后长势较好、适应性更强的品种,其中三台核桃和云光山核桃适宜在广西喀斯特地区推广种植。

【Objective】The chilling requirement of different walnut varieties city was studied,it provided a reference for developing walnut industry in karst areas in southern China.【Method】The sixteen major walnut varieties in Hechi,Gangxi were materials. Seven levels of chilling requirement were set(4 ℃ treatment for 400,500,600,700,800,900 and 1000 h),mixed buds and male buds of each variety were inserted into a bottle filled with clear water about 2 cm high and placed in a tissue culture chamber for 15 d,then the growth and growth amount of mixed bud and male flower of each walnut variety were calculated,in order to select suitable walnut varieties for promotion in karst areas.【Result】Among the 16 walnut varieties,Zhangqinghua had the lowest chilling requirement of 600 h;followed by Yunguang pecan whose chilling requirement was 700 h;the chilling requirement of Santai walnut,Xiangling,Dapao,Fengyou No.1,Lufengchun,Liaonghe No.4 and Zhangmingwei was at medium(800 h);the chilling requirement of Niangqing and Jinlongbofeng was900 h;the chilling requirement of other varieties such as Yunxin,Zhonglin No.1,Yuanlin,American pecan and Rili all exceeded 1000 h. This study also showed thatthe male flower of the same variety of walnut required more chilling requirement than mixed buds,only Xiangling and Lufengchun had 50.0% germination rate of male flowers after 900 h treatment,and the other varieties had less than 50.0% germination rate of male flowers after 1000 h treatment. In the growth of buds after germination,Santai walnut,Yunxin and Yunguang pecan showed good growth in bud after germination,Zhonglin No.1 and Yuanlin showed poor growth after germination. In the total length of bud growth,Santai walnut,Yunxin,Xiangling,Yunguang pecan,Lufengchun,Liaohe No.4,Zhangmingwei and Jinlongbofeng all reached or exceeded 5.00 cm under 1000 h. Except for Lufengchun,the total amount of bud growth of other seven varieties under 1000 h was significantly different from other treatments(P<0.05);Zhonglin No.1 and Yuanlin were only 0.50 cm under 1000 h,the differences of Zhonglin No.1 among treatments were not significant(P>0.05).【Conclusion】In the introduction of walnut varieties in Hechi,the varieties with low chilling requirement and good growth after germination and stronger adaptability should be chosen. Santai walnut and Yunguang pecan are suitable for the promotion of planting in karst areas in Guangxi.