Cell Wall Fixation,Translocation,and Vacuolar Detoxification of Cadmium Contribute to Differential Grain Cadmium Accumulation in Two Rice Cultivars

Cadmium(Cd)toxicity in rice is a major concern for human health and the environment,as it can accumulate in rice grains when grown in Cd-contaminated soils.To mitigate the risk of Cd toxicity,it is crucial to cultivate rice varieties with low grain Cd accumulation.In the summers of 2021 and 2022,we conducted Cd analysis on two rice cultivars,Tianyouhuazhan(TYHZ)and Xiushui 14,grown in fields with varying Cd pollution levels.These cultivars were also subjected to hydroponic treatment with or without 1μmol/L Cd for 7 d to assess Cd accumulation,nitric oxide(NO)production。

Effect of rice cultivar on greenhouse-gas emissions from rice-fish co-culture

In aquaculture,co-culturing rice with fish may mitigate greenhouse-gas emissions.In this study,co-culture of four rice cultivars in a laboratory-scale rice–fish system reduced CH_(4)and N_(2)O emissions relative to fish monoculture.Differences in CH_(4)and N_(2)O emissions among rice cultivars primarily stem from the differential effects of rice plants on plant-mediated CH_(4)transport,CH_(4)oxidation and nitrogen absorption.

Increasing root-lower characteristics improves drought tolerance in cotton cultivars at the seedling stage

Drought is an important abiotic stress factor in cotton production.The root system architecture(RSA)of cotton shows high plasticity which can alleviate drought-related stress under drought stress(DS)conditions;however,this alleviation is cultivar dependent.Therefore,this study estimated the genetic variability of RSA in cotton under DS.Using the paper-based growth system,we assessed the RSA variability in 80 cotton cultivars at the seedling stage,with 0 and10%polyethylene glycol 6000(PEG6000)as the control(CK)and DS treatment,respectively.An analysis of 23 aboveground and root traits in the 80 cotton cultivars revealed different responses to DS.On the 10th day after DS treatment,the degree of variation in the RSA traits under DS(5–55%)was greater than that of CK(5–49%).The 80 cultivars were divided into drought-tolerant cultivars(group 1),intermediate drought-tolerant cultivars(group 2),and drought-sensitive cultivars(group 3)based on their comprehensive evaluation values of drought resistance.Under DS,the root lengthlower,root area-lower,root volume-lower,and root length density-lower were significantly reduced by 63,71,76,and 4%in the drought-sensitive cultivars compared to CK.Notably,the drought-tolerant cultivars maintained their root lengthlower,root area-lower,root volume-lower,and root length density–lower attributes.Compared to CK,the root diameter(0–2 mm)-lower increased by 21%in group 1 but decreased by 3 and 64%in groups 2 and 3,respectively,under DS.Additionally,the drought-tolerant cultivars displayed a plastic response under DS that was characterized by an increase in the root-lower characteristics.Drought resistance was positively correlated with the root area-lower and root length density-lower.Overall,the RSA of the different cotton cultivars varied greatly under DS.Therefore,important root traits,such as the root-lower traits,provide great insights for exploring whether drought-tolerant cotton cultivars can effectively withstand adverse environments.

A telomere-to-telomere genome assembly of Hongyingzi,a sorghum cultivar used for Chinese Baijiu production

Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong reads.The 10 chromosome pairs contained 33,462 genes,of which 93%were functionally annotated.The 20 telomeres and 10 centromeric regions on the HYZ-T2T chromosomes were predicted and two consecutive large inversions on chromosome 2 were characterized.A 65-gene reconstruction of the metabolic pathway of tannins,the flavor substances in Baijiu,was performed and may advance the breeding of sorghum cultivars for Baijiu production.

Towards cultivar-oriented gene discovery for better crops

The continued expansion of the world population,increasingly inconsistent climate and shrinking agricultural resources present major challenges to crop breeding.Fortunately,the increasing ability to discover and manipulate genes creates new opportunities to develop more productive and resilient cultivars.Many genes have been described in papers as being beneficial for yield increase.However,few of them have been translated into increased yield on farms.In contrast,commercial breeders are facing gene decidophobia,i.e.,puzzled about which gene to choose for breeding among the many identified,a huge chasm between gene discovery and cultivar innovation.The purpose of this paper is to draw attention to the shortfalls in current gene discovery research and to emphasise the need to align with cultivar innovation.The methodology dictates that genetic studies not only focus on gene discovery but also pay good attention to the genetic backgrounds,experimental validation in relevant environments,appropriate crop management,and data reusability.The close of the gaps should accelerate the application of molecular study in breeding and contribute to future global food security.

Analysis on Genetic Diversity of 40 Flowering Cherry Cultivars and Construction of Molecular ID Based on SSR Markers

Studying on the genetic diversity and genetic relationship of flowering cherry cultivars is extremely important for germplasm conservation, cultivar identification and breeding. Flowering cherry is widely cultivated as an important woody ornamental plant in worldwide, especially Japan, China. However, owning to the morphological similarity, many cultivars are distinguished hardly in non-flowering season. Here, we evaluated the genetic diversity and genetic relationship of 40 flowering cherry cultivars, which are mainly cultivated in China. We selected 13 polymorphicprimers to amplify to allele fragments with fluorescent-labeled capillary electrophoresis technology. The population structure analysis results show that these cultivars could be divided into 4 subpopulations. At the population level, Na and Ne were 6.062, 4.326, respectively. Ho and He were 0.458 and 0.670, respectively. The Shannon’s information index (I) was 1.417. The Pop3, which originated from P. serrulata, had the highest Ho, He, and I among the 4 subpopulations. AMOVA showed that only 4% of genetic variation came from populations, the 39% variation came from individuals and 57% (p < 0.05) came from intra-individuals. 5 polymorphic SSR primers were selected to construct molecular ID code system of these cultivars. This analysis on the genetic diversity and relationship of the 40 flowering cherry cultivars will help to insight into the genetic background, relationship of these flowering cherry cultivars and promote to identify similar cultivars.

Effect of Different Mulch Materials on Yield and Nutrition Profile of Common Capsicum (Capsicum annuum) Cultivars in Bangladesh

Capsicum is a nutritious vegetable and its cultivation in farms is getting popular in Bangladesh. Although many efforts have lain to explore better yielding and nutritionally rich cultivars with suitable modern cultivation techniques but still have to find the desired outcome. Thus, it’s necessary to conduct further research to identify the high-yielding and nutritious capsicum cultivars in Bangladesh. An experiment was conducted from July 2021 to June 2022 at the Bangladesh Institute of Research and Training on Applied Nutrition (BIRTAN) research field with three cultivars of capsicum: B0 = California Wonder, B1 = BARI Misti Morich-1 and B2 = BARI Misti Morich-2 and three mulching: T0 = No mulching, T1 = Water hyacinth, T2 = Poly Mulching in randomized complete block design with three replications to identify better quality capsicum cultivar and suitable mulching material. Among cultivars the BARI Misti Morich-2 (B2) showed increased agronomic parameters like number of branches and effective branches per plant, leaves length and width, consequently yield and yield contributing traits were also enhanced like fruits per plant, fruit length, fruit diameter and yield per plant (25.97%, 4.54%, 3.64% and 21.43%, respectively). Poly Mulching (T2) increased agronomic traits, yield traits and yield (0.61 kg) than BARI Misti Morich-1 (T1). The combined effect of B2T2 increased the number of branches per plant, effective branches per plant, leaves length and breadth by 40%, 90%, 15.57% and 26.22%, respectively, hence resulting in an increased yield of 20%. BARI Misti Morich-2 cultivar showed an increase in Fe, Zn and Vitamin-C content of 26.24% and 23.10%, 8.82% and 5.14%, and 6.03% and 5.74% than B0 and B1 cultivars, respectively. Therefore, BARI Misti Morich-2 exhibited the improved agronomic, yield and nutritional traits of capsicum under poly mulching among other cultivars in Bangladesh.

Study on Germplasm Resources of Peach Cultivars

[Objectives]To study the germplasm resources of excellent peach cultivars.[Methods]Five peach cultivars were introduced,in-cluding‘Jinxiu’peach,‘Jinxiang’peach,‘Chunxiao’peach,‘Hujingmilu’peach and‘018 nectarine’peach.Then,these five cultivars were used to study the biological characteristics of peach trees,namely,as phenology,fruit quality,heat resistance,cold resistance and other resistance.[Results]Five cultivars of peach plants grew fast and robust,among which‘018 nectarine’had very crisp fruit,‘Jinxiu’,‘Jinxiang’,‘Chunxiao’and‘Hujingmilu’had very sweet fruitꎻthe peach trees of these five cultivars have good water resistance,heat resist-ance and cold resistance.[Conclusions]The results of this study can not only provide a reference for the introduction of peach trees,but also provide a practical basis for the large-scale planting of peach trees.

Skim resequencing finely maps the downy mildew resistance loci RPF2 and RPF3 in spinach cultivars whale and Lazio

Commercial production of spinach(Spinacia oleracea L.)is centered in California and Arizona in the US,where downy mildew caused by Peronospora effusa is the most destructive disease.Nineteen typical races of P.effusa have been reported to infect spinach,with 16 identified after 1990.The regular appearance of new pathogen races breaks the resistance gene introgressed in spinach.We attempted to map and delineate the RPF2 locus at a finer resolution,identify linked single nucleotide polymorphism(SNP)markers,and report candidate downy mildew resistance(R)genes.Progeny populations segregating for RPF2 locus derived from resistant differential cultivar Lazio were infected using race 5 of P.effusa and were used to study for genetic transmission and mapping analysis in this study.Association analysis performed with low coverage whole genome resequencing-generated SNP markers mapped the RPF2 locus between 0.47 to 1.46 Mb of chromosome 3 with peak SNP(Chr3_1,221,009)showing a LOD value of 61.6 in the GLM model in TASSEL,which was within 1.08 Kb from Spo12821,a gene that encodes CC-NBS-LRR plant disease resistance protein.In addition,a combined analysis of progeny panels of Lazio and Whale segregating for RPF2 and RPF3 loci delineated the resistance section in chromosome 3 between 1.18–1.23 and 1.75–1.76 Mb.This study provides valuable information on the RPF2 resistance region in the spinach cultivar Lazio compared to RPF3 loci in the cultivar Whale.The RPF2 and RPF3 specific SNP markers,plus the resistant genes reported here,could add value to breeding efforts to develop downy mildew resistant cultivars in the future.

Gene expression pattern of K transporter GhHAK5 gene of potassium efficient and in-efficient cotton cultivars based on morphological physiognomies as affected by potassium nutrition and reduced irrigation

Background Under K deficiency the uptake and distribution pattern in plant cells is mediated through different transport proteins and channels which were controlled by specific gene family.Therefore,a hydroponic experiment was conducted under control condition for testing the gene expression pattern of the K transporter under adequate and low K supply levels.After that,a 2-year field experiment was conducted to evaluate five selected cotton cultivars(four K-efficient cultivars,viz.,CIM-554,CYTO-124,FH-142,IUB-2013,and one K non-efficient,BH-212) screened from the initial hydroponics culture experiment and two levels of potassium(0 K_(2)O kg·ha^(-1) and 50 K_(2)O kg·ha^(-1)) were tested under reduced irrigation(50% available water content;50 AWC) and normal irrigation conditions(100% available water content;100 AWC).Result Results revealed that the transcript levels of GhHAK5aD in roots were significantly higher in K^(+) efficient cultivars than that in K^(+) non-efficient cultivars.The GhHAK5aD expression upon K^(+) deficiency was higher in roots but lower in shoots,indicating that GhHAK5aD could have a role in K^(+) uptake in roots,instead of transport of K^(+) from root to shoot.Similarly,under field conditions the cultivar FH-142 showed an increase of 22.3%,4.9%,2.4%,and 1.4% as compared with BH-212,IUB-2013,CYTO-124,and CIM-554,respectively,in seed cotton yield(SCY) with K application under reduced irrigation conditions.With applied K,the FH-142 showed an increase in net photosynthetic rate by 57.3% as compared with the rest of the cultivars under reduced irrigation over K control.However,the overall performance indicators of K-efficient cultivars like FH-142,CYTO-124,CIM-554,and IUB-2013 were better than BH-212(K in-efficient) under reduced irrigation conditions with applied K at 50 kg·ha^(-1).Fiber quality trait improved significantly with K application under water deficit.The increase in micronaire was 3.6%,4.7%,7.8%,3.4%,and 6.7% in BH-212,IUB-2013,CIM-554,CYTO-124,and FH-142,respectively,with K application at 50 kg·ha^(-1) over without K application under reduced irrigation conditions during the cotton growing season.Similarly,the cultivars FH-142 increased by 12% with K application under reduced irrigation as compared with other cultivars.The performance of K-efficient cultivars under reduced irrigation conditions was 30% better in SCY and quality traits with the application of K at 50 kg·ha^(-1) as compared with K-non-efficient cultivars.Similarly,water use efficiency(WUE)(40.1%) and potassium use efficiency(KUE)(20.2%) were also noted higher in case of FH-142 as compared with other cultivar with K application under reduced conditions.Conclusion Higher expression of GhHAK5aD gene was observed in K-efficient cultivars as compared with K-nonefficient cultivars in roots indicates that GhHAK5aD may be contributing to genotypic differences for K^(+) efficiency in cotton.K-efficient cotton cultivars can be used for the low-K environments and can also be recommended for general cultivars.

Mixing trait-based corn(Zea mays L.)cultivars increases yield through pollination synchronization and increased cross-fertilization

Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.).Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a potential means of mitigating yield losses under stress conditions.We conducted a three-year field study to investigate the effects of cultivar mixtures on kernel setting rate,pollen sources,and yield.This study consisted of six treatments,including two high temperature-tolerant(HTT)monocrops of WK702 and DH701,two high temperature-sensitive(HTS)monocrops of DH605 and DH662,and two HTT–HTS mixtures of WK702-DH605 and DH701-DH662.The anthesis–silking interval(ASI)was 0.9–1.6 days shorter in mixtures than in monocrops.Kernel setting rate was increased in mixtures(86.4%–88.7%)compared with those in monocrops(74.7%–84.1%)as a result of synchrony and complementarity of pollination.Grain yields of the HTT–HTS mixtures increased by 13.3%–18.7%,equivalent to 1169 to1605 kg ha^(-1),in comparison with HTS corn monocrops.The results of SSR markers showed that crossfertilization percentage in corn cultivar mixtures ranged from 29.3%to 47.8%,partially explaining yield improvement.Land equivalent ratio(LER)was 1.12 for corn mixtures and the partial land equivalent ratio(e.g.,>0.5)showed the complementary benefits in corn mixtures.The results indicated that mixing corn cultivars with diverse flowering and drought-tolerance traits increased yields via pollination synchrony.

Stay-Green Panicle Branches Improve Processing Quality of Elite Rice Cultivars

Rice panicle branches are key routes for transportation of photo synthetic products to grains.Branch senescence is an important trait that the breeders considered when breeding elite rice cultivars in South China.However,little is known about the mechanisms underlying the contributions of stay-green panicle branches to rice yield and quality.Here,we reported stay-green branches that continuously maintained transportation function and provided carbohydrates for basal grain development at the late stages of rice development.This ensured the coordination of development between apical and basal grains,and further improved the processing quality of elite rice.These findings provided strategies for improving the fullness and quality of rice grains and presented an important basis for cultivating elite rice.

Genetic diversity, population structure, and genome-wide association analysis of ginkgo cultivars

Ginkgo biloba is an economically valuable tree worldwide.The species has nearly become extinct during the Quaternary,which has likely resulted in reduction of its genetic variability.The genetic variability is now conserved in few natural populations in China and a number of cultivars that are,however,derived from a few ancient trees,helping the species survive in China through medieval times.Despite the recent interest in ginkgo,however,detailed knowledge of its genetic diversity,conserved in cultivated trees and cultivars,has remained poor.This limits efficient conservation of its diversity as well as efficient use of the existing germplasm resources.Here we performed genotyping-by-sequencing(GBS)on 102 cultivated germplasms of ginkgo collected to explore their genetic structure,kinship,and inbreeding prediction.For the first time in ginkgo,a genome-wide association analysis study(GWAS)was used to attempt gene mapping of seed traits.The results showed that most of the germplasms did not show any obvious genetic relationship.The size of the ginkgo germplasm population expanded significantly around 1500 years ago during the Sui and Tang dynasties.Classification of seed cultivars based on a phylogenetic perspective does not support the current classification criteria based on phenotype.Twenty-four candidate genes were localized after performing GWAS on the seed traits.Overall,this study reveals the genetic basis of ginkgo seed traits and provides insights into its cultivation history.These findings will facilitate the conservation and utilization of the domesticated germplasms of this living fossil plant.

Characterization of wheat monogenic lines with known Sr genes and wheat cultivars for resistance to three new races of Puccinia graminis f. sp. tritici in China

Wheat stem rust, caused by Puccinia graminis f. sp. tritici(Pgt), is a potentially devastating fungal disease of wheat worldwide. The present study was to evaluate the resistance of 42 wheat monogenic lines with known stem rust resistance(Sr) genes and 69 wheat cultivars to three new Pgt races(34C0MRGQM, 34C3MKGQM, and 34C6MTGSM)identified from aeciospores at the seedling and adult-plant stages. The phenotyping results revealed that monogenic lines harboring resistance genes Sr9e, Sr17, Sr21, Sr22, Sr26, Sr30, Sr31, Sr33, Sr35, Sr36, Sr37, Sr38, Sr47, SrTmp,and SrTt3 were effectively resistant to all three Pgt races at the seedling and adult-plant stages. In contrast, monogenic lines containing Sr5, Sr6, Sr7b, Sr9a, Sr9d, Sr9f, Sr9g, Sr9b, Sr16, Sr24, Sr28, and Sr39 were highly susceptible to these races at both seedling and adult-plant stages. The other lines with Sr8a, Sr10, Sr11, Sr13, Sr14, Sr15, Sr18, Sr20,Sr19, Sr23, Sr25, Sr27, Sr29, Sr32, and Sr34, displayed variable levels of resistance to one or two of the tested races.Seedling infection types(ITs) and adult-plant infection responses(IRs) indicated that 41(59.4%) of the wheat cultivars showed high resistance to all the three races. Molecular marker analysis showed that four wheat culitvars likely carried Sr2, 20 wheat culitvars likely carried Sr31, 9 wheat culitvars likely carried Sr38, and none of the cultivars carried Sr24,Sr25, and Sr26. Our results provide a scientific basis for rational utilization of the tested Sr genes and wheat cultivars against these novel Pgt races.

基于多元统计分析评价不同茶树品种的绿茶适制性

采用主成分分析和多元线性回归分析法考察不同茶区优选区域适制茶树品种的绿茶适制性。本研究以种植于同一区域的63个茶树品种鲜叶为原料,按同一加工工艺加工成烘青绿茶,分析其感官品质、主要理化品质(茶多酚、游离氨基酸、水浸出物和叶绿素)和色度值(L*、a*、b*),结合主成分分析和多元线性回归分析,评价供试品种的绿茶适制性及其主要影响因子。结果表明,不同品种绿茶叶绿素含量的变异系数最大(26.7%),其次是干茶色度值a*值(22.2%)、汤色(17.1%)和干茶色泽评分(16.2%)。各指标相关性分析表明,茶多酚含量与干茶色泽、汤色和叶底色泽之间,干茶叶绿素含量、|a*|值、b*值与干茶色泽之间,干茶叶绿素含量、|a*|与叶底色泽之间,干茶|a*|值、b*值与汤色之间极显著相关(P<0.01)。主成分分析结果表明,前5个主成分贡献率达76.895%,第1主成分贡献率为31.918%,主要指向色泽品质。通过前5个主成分构建评价模型,得到排名前10的品种包括:中茶108、乌牛早、平阳特早、蒙山9号、薮北种、福鼎大白、鸠坑16号、福鼎大毫、茂绿、龙井43。以主要理化品质和感官评价总分为对象进行多元线性回归分析,得到回归函数为:Y=68.668+5.174x,其中Y为感官评分总分,x为|a*|值,R2为0.313(P<0.001)。以此函数得到排名前10的品种与主成分分析结果高度一致,表明a*值是评定绿茶适制品种的重要指标,可作为绿茶适制品种筛选的重要依据。

抗旱丰产春小麦新品种陇春43号选育报告

为甘肃省小麦生产提供抗旱、抗病、丰产、优质小麦新品种,以促进小麦更新换代,实现小麦稳产增产,以衡7728为母本、陇春27号为父本进行了有性杂交,通过异地生态选择、采用系谱法成功选育出了抗旱丰产春小麦新品种陇春43号。2018—2019年参加甘肃省旱地春小麦区域试验,平均折合产量3074.70 kg/hm^(2),较对照品种西旱2号增产10.02%。2020年参加甘肃省旱地春小麦生产试验,平均折合产量3582.61 kg/hm^(2),较对照品种西旱2号增产9.81%。该品种具有高产稳产,优质,株型紧凑,抗旱,抗倒伏,中抗条锈和白粉病等特点,适宜在甘肃省中部旱地春麦区以及类似生态地区种植。

中熟杏新品种国锦的选育

国锦是以中国地方品种串枝红为母本、国外育成品种金太阳为父本人工杂交选育而成的中熟杏新品种。果实椭圆形,平均单果质量112.0 g,大果质量138.2 g;果顶平或微凹,梗洼浅而广,缝合线中深;果皮底色橙色,果实盖色红色;果肉橙色,硬溶质,风味浓郁、酸甜适中,品质上;可溶性固形物含量(w,后同)为13.6%,可溶性糖含量为9.4%,可滴定酸含量为1.3%,维生素C含量为6.4 mg·100 g^(-1),硬度为2.0 kg·cm^(-2),常温下可贮藏5~7 d。在辽宁省熊岳地区4月上旬开花,6月下旬果实成熟,果实发育期75 d左右。以短果枝结果为主,萌芽率55.7%,成枝力弱。中抗细菌性穿孔病和流胶病,抗寒性强。适宜在辽宁以南的全国杏产区栽培,早期丰产性好,4年生树进入盛果期,每666.7 m2产量可达2398kg,连续丰产能力强。

两个香榧新品种美人指和早珍珠的选育

美人指和早珍珠是2023年从浙江省嵊州市实生榧树中选育出的两个新品种,采用穗条嫁接方式繁育子代。美人指种实质量10.77 g,呈卵球形,种形指数1.69,鲜出核率26.8%,种核质量2.89 g,核形指数2.74,种核细长、种壳较薄,干核出仁率72.54%,种仁含油率59.1%,蛋白质含量(w,后同)13.1%,可溶性糖含量2.94%。早珍珠种实质量7.98 g,呈圆球形,种形指数1.21,鲜出核率33.7%,种核质量2.69 g,核形指数1.75,呈近卵球形,种壳极薄,干核出仁率达78.68%,种仁含油率57.6%,蛋白质含量11.0%,可溶性糖含量4.17%。两个品种在炒制加工后,均表现出极易脱衣、质地松脆、后味香甜、综合口感佳的特点,推广应用前景广阔。美人指4月上旬开花,种实9月上旬成熟;早珍珠花期较早,于3月下旬开花,10月上旬种实成熟,成熟期较迟。子代测定结果表明,两个品种的种实性状、种仁风味与母株表现一致,且早实性、丰产性和稳产性良好,适宜在浙江省及相似环境地区栽培。

马铃薯新品种北方008的选育

北方008是以春薯2号为母本、中薯5号为父本,通过有性杂交选育而成的中晚熟马铃薯新品种。该品种生长势强,株型类型为直立型,从出苗到成熟100 d。薯块扁圆形,薯皮淡黄色,薯肉白色,薯皮略麻,芽眼浅,结薯集中。单株结薯数6.5个,单株块茎质量0.90 kg,大、中薯率77.5%。平均667 m^(2)产量2439.62 kg。块茎干物质含量(w,后同)13.9 g·100 g^(-1)、淀粉含量11.9 g·100 g^(-1)、还原糖含量0.53 g·100 g^(-1)、粗蛋白含量1.4 g·100 g^(-1)、维生素C含量25.3 mg·100 g^(-1)。对晚疫病表现高抗;抗马铃薯X病毒(potato virus X,PVX)、马铃薯Y病毒(potato virus Y,PVY)。2020年通过农业农村部非主要农作物品种登记。

不同品种山核桃幼苗叶片光合及叶绿素荧光特性的比较分析

为了给不同品种山核桃高效栽培提供科学依据,开展5个山核桃品种幼苗叶片光合及叶绿素荧光特性的比较分析来筛选高光效品种,以2年生山核桃为研究对象,采用光合测定仪(LI-6800)及叶绿素荧光仪(MINI-PAM-Ⅱ)测定5个品种山核桃的叶片光合及叶绿素荧光特性,进行相关性分析,并利用隶属函数法对光合能力进行综合评价。相关性分析结果显示:5个山核桃品种P_(n)、C_(i)、G_(s)、T_(r)、WUE等指标均达到极显著差异;净光合速率与G_(s)、T_(r)呈极显著正相关,C_(i)与G_(s)、Y_(II)呈显著性正相关,与qP呈显著性负相关。隶属函数分析表明,供试品种的光合能力依次为:宁国山核桃2号>宁国山核桃4号>宁国山核桃3号>宁国山核桃5号>宁国山核桃1号。可见5个山核桃品种光合特性存在差异。宁国山核桃2号和3号光合能力较强,蒸腾速率较高,水分利用率低,生产中宜选择水肥条件较好的造林地;宁国山核桃4号耗散过剩光能热量的能力最强,具有较高的光保护能力,其他山核桃品种幼林期建议间作高杆玉米等适度遮阴。