板栗低干矮冠多主枝开心形树体结构评价

为探讨低干矮冠多主枝开心树形对板栗产质性能的影响,以10年生‘金丰’板栗为试材,采用将整树冠层分层的方法,研究了低干矮冠多主枝开心树形的树体结构参数及不同冠层间板栗总苞的分布特征。结果表明:在垂直方向上,结果枝和总苞的分布主要集中在树体的中上部,下部有少量分布,其中结果枝和总苞均在1.0~1.5 m层间最多,而每果枝总苞数量在冠层两端最多。在水平方向上,发育枝、结果枝和总苞数量随冠层外移逐渐增多,集中分布于0.5~2.5 m的冠层范围,分别占总量的87.9%、89.9%和88.2%,其中结果枝和总苞在1.5~2.0 m的层间数量最多,体现了该树形立体结果的效果。该树形在保证坚果品质的同时,产量较自然开心形和自然圆头形提高30%以上。

Evaluation of structure characteristics of low-trunk,dwarf-crown,multi-branch and open-center tree form of chestnut

In order to research the influences of the low-trunk, dwarf-crown, multi-branch and open-center tree form on yield and quality of chestnut, taking 10-year-old chestnut variety ‘Jinfeng’ as test materials, some structure parameters of this tree form and involucre distribution characteristics in different crown layers were studied, using the method of dividing crown into many layers. The results showed that the bearing branches and involucres mainly distributed in the upper and middle layers at vertical direction, and there was a little in the lower layers. Both bearing branches and involucres mainly distributed in the 1.0-1.5 m crown layer, while involucre number per bearing branch was the most at the top and bottom of the crown layer. At horizontal direction, developing branch number, bearing branch number, and involucre number were gradually increased from the center to outward of the crown layer, and mainly distributed in the 0.5-2.5 m crown layer, which accounted 87.9%, 89.9% and 88.2% of the total, respectively. Number of bearing branches and involucres was the most in the 1.5-2.5 m crown layer. So the effect of all-directional fruiting could be realized. At the same time of keeping nut quality, nut yield of the new tree form could be increased over 30% than those of natural open-center form and natural spherical form.