梨树生长和果实品质指标对水氮耦合响应及关联度分析

Responses of Pear Tree Growth and Fruit Quality Indexes to Water and Nitrogen Coupling and Correlation Degree Analysis

为探究水、氮对梨树生长和果实品质指标影响,分析水氮耦合处理下梨树生长与各果实品质指标间关联程度,开展了为期1年的田间试验,试验设定2因素2水平,亦即2个灌水下限(W1:75Fc,W2:65Fc)和2个施N水平(F1:324 kg/hm^2,F2:168 kg/hm^2),共4个试验处理(低水低肥:W1F1;低水高肥:W1F2;高水低肥:W2F1;高水高肥:W2F2)。试验过程中量测了梨树营养生长指标(新梢长度、新梢基径、叶面积及叶绿素含量)和果实品质指标(单果重量、可溶性固形物含量、还原型Vc含量及可滴定酸含量),结果表明:水氮耦合对黄金梨树生长指标和果实品质指标都有一定影响,但规律不尽相同,提高灌水下限和增加施氮量能显著增加新梢长度和基径,但叶片面积和叶绿素含量对水氮耦合方案响应较为复杂,不存在单向递增关系;单果重量对灌水下限的响应最为明显,其他2个品质指标对施氮量响应较为明显,提高灌水下限和增加施氮量能提高单果重量和降低可滴定酸含量,但可溶性固形物和还原型Vc含量对水氮耦合响应较为复杂,受水氮交互作用影响显著。果实品质指标与梨树生长指标存在一定关联性,相比而言,梨树新梢长度和基径对多数品质指标贡献度最大。因此,将灌溉施肥管理与农艺管理相结合,协调梨树各器官对养分的吸收和分配关系,进而优化新梢生长量,促进梨果品质的提高。

In order to explore the effects of water and nitrogen on pear growth and fruit quality indexes,and to analyze the indexes of pear tree growth and fruit quality indexes with different coupled water and nitrogen treatments,a one-year field test with two factors and two levels was carried out.That was,two irrigation limits(W1:75%Fc,W2:65%Fc)and two nitrogen application levels(F1:324 kg/hm^2,F2:168 kg/hm^2),a total of 4 test treatments(low water and low fertilizer:W1F1;low water and high fertilizer:W1F2;high water and low fertilizer:W2F1;high water and high fertilizer:W2F2).During the test,the vegetative growth indicators(new shoot length,new shoot base diameter,leaf area and chlorophyll content)and fruit quality indicators(single fruit weight,soluble solid content,reduced Vc content,and titratable acid)of the pear were measured.The results showed that water and nitrogen coupling had some effects on the vegetative growth index and fruit quality index of Golden Pear,but the rules were not exactly the same.Increasing the irrigation water limit and the amount of nitrogen application could significantly increase the new shoot length and base diameter.However,the response of the leaf area and chloro-phyll content to the water and nitrogen coupling scheme was more complicated,and there was no one-way increasing relationship;the weight of a single fruit responded most significantly to the irrigation water limit,and the other two quality indicators responded more significantly to the amount of nitrogen applied.Increasing the irrigation limit and nitrogen application could increase the weight of single fruit and reduce the content of titratable acids,but soluble solids and reduced Vc content had a more complex response to water-nitrogen coupling and were significantly affected by water-fertilizer interaction.The fruit quality index had some correlation with the growth index of the pear tree.In comparison,the new shoot length and base diameter of the pear tree contributed the most to most quality indexes.Therefore,it is suggested that combining irrigation and fertilization management with agronomic management to coordinate the nutrient absorption and distribution relationship of pear organs,thereby optimizing the growth of new shoots and promoting the improvement of pear fruit quality.