Self-incompatibility (SI) is an important mechanism for the prevention of self-fertilization in plants and is one of the major causes of seedlessness in citrus plants. Phospholipase D (PLD) is closely related to the growth and development of pollen, but the role of PLD in citrus plants during SI is poorly understood. In this study, we identified PLDs associated with SI in citrus plants, analyzed 15 C2-PLDs encoding homologs of the C2 domain in the genomes of sweet orange (Citrus sinensis) and clementine mandarin (Citrus clementina). We performed a phylogenic analysis to classify the PLD subfamilies of homologous genes from other species and found that the C2-PLDs of ‘Xiangshui’ lemon shared high homology with C2-PLDs from pear and Arabidopsis. Expression analysis revealed that ClPLD5 is probably involved in the regulation of pollen of ‘Xiangshui’ lemon during SI. ClPLD5 is enriched in pollen and functions as a pollen protection factor, as overexpression of ClPLD5 in self-incompatible pollen prevented the depolymerization of the actin cytoskeleton during SI. This work provides insights into the regulation of the cytoskeleton in pollen under SI challenge in citrus plants, in which PLD plays a protective role in incompatible pollen. A C2-PLD gene (ClPLD5) related to self-incompatibility was identified within the “Xiangshui” lemon C2-PLD family, and overexpression of the ClPLD5 gene in pollen increased the stability of the pollen cytoskeleton under self-incompatibility challenge.

Gametophytic self-incompatibility (GSI) is an important factor affecting fruit development and is one of the important mechanisms of seedlessness in citrus. Although many studies have investigated the mechanisms of SI, this process remains unclear in “Xiangshui” lemon (C. limon). In this study, we cloned one S-RNase homologous gene and one SLF homologous gene from the “Xiangshui” lemon, designated as ClS1 (pistil-specific expression) and ClF-box (pollen-specific expression), which contain open reading frames (ORFs) of 534 and 810 bp, respectively. The expression pattern of these two genes was analyzed by quantitative real-time polymerase chain reaction, and the results showed that the expression pattern of these two genes was significantly upregulated after self-pollination compared to that after cross-pollination. Through pollination in transgenic tobacco, we found that the pollen tubes grew slowly and became twisted after cross-pollination of ClS1♀ and ClF-box ♂ transgenic tobaccos, but the pollen tubes of control, self-pollination ClS1 and cross-pollination ClS1♂, and ClF-box ♀ grew normally. Furthermore, significantly fewer pollen tubes of ClS1♀ and ClF-box ♂ entered the ovules than that in other combinations, and the seed number of cross-pollination ClS1♀ and ClF-box ♂ transgenic tobaccos was significantly reduced. These results indicated that the ClS1 and ClF-box genes contribute to the self-incompatibility of the “Xiangshui” lemon.

以3年生枳砧建阳桔柚为试材,观察花器官结构、花粉育性、授粉后花粉管生长过程和早期胚胎发育情况。结果表明,建阳桔柚的花为完全花,花粉染色活力为66.42%,花粉萌发率为8.68%。自花和异花(沃柑花粉)授粉4h后花粉都开始萌发;授粉8h后异花授粉的花粉大量萌发,自花授粉萌发量比授粉4h时多,但低于异花授粉;异花授粉24h后少量花粉管伸入子房,异花授粉48h后大量花粉管进入子房中且部分完成受精;自花授粉48h后花粉管进入子房,但并没有受精成功,自花授粉72h后可观察到少量受精成功。自花授粉于授粉2周后观察到胚珠内部出现空腔、早期败育;异花授粉于授粉3周后观察到部分胚珠内部出现空腔、早期败育。

【Objective】This study investigated correlation between bearing shoot and flower formation of different blueberry varieties,in order to provide reference for blueberry cultivation in Guangxi.【Method】Three blueberry varieties from Tian’e county,Guangxi were used as materials（Misty,Legacy and Premier）.Length,diameter,leaf number,lateral bud number,terminal bud number and total bud number of the longest and the shortest bearing shoots were assessed.Correlation between the characters as well as correlation between the characters and flower formation were analyzed.【Result】According to regression analysis,regression equation for Misty total bud number（y）,shoot length（x;）and leaf number（x;）was=1.632+0.052x;-0.026x;,regression equation for Legcy total bud number（y）,shoot length（x;）and shoot diameter（x;）was=1.061+0.009x;+0.152x;,regression equation for Premier total bud number（y）,shoot leaf number（x;）,shoot diameter（x;）,leaf number（x;）was=-3.201+0.086x;+0.267x;+0.360x;.Correlation analysis on the characters showed that,blueberry shoot length,shoot diameter and leaf number were significantly correlated（P<0.05,the same below）;total bud number,shoot length,shoot diameter and leaf number were significantly correlated.But the correlation coefficient differed for different varieties.【Conclusion】Length,diameter and leaf number of blueberry bearing shoot have significant influence on total bud number.In actual planting,bearing shoots quality and total bud number can be increased through controlling shoot length,shoot diameter and leaf number via proper pruning and fertilization.In this way,the yield and quality of blueberry can be improved.

Seedlessness is a very important characteristic of Xiangshui lemon, which is mainly caused by self-incompatibility. In order to further understand the genetic mechanism of the self-incompatibility of Xiangshui lemon, a length of 1 357 bp F-box gene was cloned by RT-PCR which was named LFB2 with lemon leaves as materials in this study on the basis of F-box gene fragment obtained by De Novo. Bioninformatics analysis showed that this gene encoded 446 amino acids, contained two WD domains at the C-terminal of the amino acid, and belonged to the FBXW protein, of which the protein molecular weight was 111.62 kD and the isoelectric point was8.97. The LFB2 expression in different flower organs was analyzed by q RT-PCR, and the results indicated that the gene was expressed highest in the stamens, which was about 10 times as much as that in other flower organs; Also,under adversity stress, the gene expression changed significantly. These results showed that LFB2 gene played a role in the growth and development of pollen and under stress environment.

In this study, the fruits of Annona squamosa L. picked in the orchard of Guangxi University was used to study the relationship between the seed development and fruit skew individual and quality of custard apple（Annona squamosa L.）. Data were analyzed by means of biological statistical software and the result provided a theoretical reference with reducing the degree of deflection and improving the fruit quality of custard apple. The results showed that there was very significant negative correlation（ p<0.01） among transverse diameter, longitudinal diameter, fruit weight and degree of skewness; and there was also significant negative（ p<0.05） correlation among seed numbers,seed weight and degree of skewness. Path analysis and multiple stepwise regression analysis between seed and fruit characters and degree of skewness was carried out and the result suggested that the main impact factors on the degree of skewness were the development of transverse diameter of the fruit, followed by the number of seed.Other factors affected the degree of skewnes by influencing the development of the transverse diameter and the number of seed. The regression equation: Y =0.785-0.005X;-0.003X; was established（ Y for the degree of skewness, X; for the transverse diameter, X; for the seed numbers）; Fruit with good formation apparently showed higher advantage in single fruit weigh, total soluble solid, vitamin C and edible rate than the deformation and lopsided fruits. There was also a significant difference between good fruits and lopsided fruits in vitamin C and edible rate. This study indicated the direction of the corresponding agronomic measures to prevent and control the fruit deviation in the process of fruit growth, and it had practical significance to improve the quality of the fruit.

The indexes of ‘Fenglishijia’fruit including the shape factors,weight and soluble solids content( SSC)were measured,principal component analysis and clustering analysis were used to set up the standard quality grading of fruits of ‘Fenglishijia’by SPSS,the aim of this study was to provide reference for quality classification of ‘Fenglishijia’fruit. Results showed that fruit skewness degree coeffient of variation was the largest,and thickness in large part of lopsided fruit coefficient of variation was the smallest for all the studied indexes. There was close correlation among fruit shapes and they were also highly related to the single fruit quality. SSC is extremely significant positively related to single fruit weigt,and extremely significant negatively related to skewness degree. Principal component analysis and clustering analysis showed that the standard quality grading of fruits of‘Fenglishijia’should be mainly based on single fruit weight and other indexes that represents fruit size,and the assistant factors should be based on the fruit shape index and the skewness index that represents the fruit shape and the degree of skewness,respectively.

This study was to observe morphology of pollen under SEM and the pollination compatibility of two cultivars of atemoya(Annona cherimoya × A.squamosa),African Pride and Fenglishijia,in order to provide a scientific basis to the cultivation and hybrid breeding of atemoya.Morphology of pollen under SEM and growth of pollen tubes in the styles of atemoya and the fruit setting after self-and cross-pollination was examined.Results showed that African Pride and Fenglishijia exhibited similar pollen morphology.For both cultivars,the shape of pollen was actinomorphy,and the ornamentation of exine was cave-shaped.African Pride presented an oval shape in equatorial view and round in polar view,similar to those of Fenglishijia.Pollens of two cultivars germinated from both self-and cross-pollination.However,the timing of pollen germination between African Pride and Fenglishijia was different.Large number of pollen tubes presented in Fenglishjia at 1hafter pollination,but 14 hafter pollination in African Pride.The pollen tubes of all self-and cross-pollination were observed to reach the ovary 24 hafter pollination.The pollen tubes reached ovule in Fenglishijia 48 hafter pollination.We proposed that African Pride and Fenglishijia have similar pollen morphology with good compatibility under self-and cross-pollination.

To investigate the causes and control method of kumquat fruit drop in high temperature,to carry out high-temperature suppression kumquat fruit drop test.By to investigating the temperature,it is found that the temperature is an important factor leading to fruit drop,which in turn carried out to six groups of different nutrients and growth regulator composition comparative test.Results show:30mg/l 920+5mg/l 2,4-D+Brassinolide 2,000 times,brassinolide 2000 times+30mg/l 920+Longhorned beetle cream and sugar alcohols liquid calcium +polymeric boron+longhorned beetle cream processing signicantly reduced fruit drop.It is showed that auxin and nutrients can effectively reduce the fruit drop caused by high temperatures.

Fresh red pitaya was soaked in different concentrations of composite coating agents of sucrose-based polymers and sodium alginate for 1 min, and then stored at room temperature(29~31 ℃) for 11 days, in order to study the effects of different complex coating agents on preservation quality of red pitaya during storage. The results showed that, the film coating treatments could effectively reduce the evaporation of fruit water and weight loss rate, delay the decline of contents of soluble solids, titratable acid, soluble sugar and soluble protein. Under normal storage conditions,red pitaya could store for 8 ~9 days, and prolonged the shelf life for 2 ~4 days compared with the control(water treatment). Among them, the treatment of 5% sucrose-based polymers +1% sodium alginate had the best preservation effect, appeared rotten fruit after 7 days storage, and postponed 4 days compared with the control.

[Objective] To determine the reasonable cultivation period for atemoya,and to establish the mathematical model of the growth of fruits of this variety. [Method] We detected the fruit longitudinal diameter,transverse diameter,fruit stalk length and width during the fruit growth and development of atemoya,and to establish the fruit growth model of atemoya. [Result]Atemoya fruit transverse diameter and longitudinal diameter had a growth peak on 28 days after pollination. Fruit diameter growth rate was significantly faster than the transverse diameter during the period of rapid growth. Fruit stalk width growth and elongation growth during this period also showed a rapid growth trend. Fruit size and Fruit stalk growth were both at a slow growth period on 56 d after pollination. Synchronization growth was observed for fruit and fruit stalk development. The correlation coefficient of each index was greater than 0. 980 00. The regression equation of the correlation coefficient between day number after pollination and each index was greater than 0. 970 00. [Conclusion]There are obvious polynomial regression relations among atemoya fruit transverse and longitudinal diameters,stalk length,stalk width and growth days after pollination,and the mathematical model of the growth process is also a cubic equation. This mathematic model has good fitting,and can better reflect the dynamic changes of fruit and stalk development.

[Objective]The aim was to study effects of mixed chemicals on defoliation rate of Annona squamosa after harvesting.[Method]Defoliant trichloroacetic acid(TCA) + kalium jodatum(KI) + ethephon(ETH) thidiazuron(TDZ) was designed by using an orthogonal experimental with four factors and three levels for spraying after harvest and the effect of the defoliant on defoliation rate of Annona squamos cv. African pride were studied.[Result] The result showed that spraying with the defoliant(1. 0 g/L TCA + 3 g/L KI + 12% ETH + 5 g/L TDZ) in the first 7d after harvest pruning can basically remove the leaf of Annona squamosa with defoliation rate as 92. 04%,which is conducive to the development of post harvest pruning work and promoting the germination of branches.[Conclusion]The medicament combination of 1. 0 g/L TCA + 3 g/L LKI +12% ETH + 5 g/L TDZ has the best defoliation effect.

以玫红肉火龙果、粉红肉火龙果、紫红肉火龙果、白肉火龙果4种火龙果种子为试验材料,进行火龙果种子萌发特性比较试验研究。试验结果表明,不同果肉颜色的火龙果,其种子萌发率不同。不同浸种时间,其种子萌发率也不同。紫红肉火龙果种子的发芽率、发芽势和活力指数最大,粉红肉火龙果种子刚好相反,白肉火龙果种子和玫红肉火龙果种子处于两者之间,其中白肉火龙果种子的发芽率和发芽势都高于玫红肉火龙果种子,但其活力指数却低于玫红肉火龙果种子。4种不同果肉颜色火龙果种子的最佳浸种时间分别是:玫红肉火龙果种子,为24h;粉肉火龙果种子,为36h;紫红肉火龙果种子,为36h;白肉火龙果种子,为36h。

In order to obtain high-quality RNA from lemon,5 methods for RNA extraction from different Xiangshui lemon tissues were evaluated upon time and cost consumption,yield and quality of RNA isolated,to select the best method to extract RNA from lemon tissues.The results showed that the modified HuaY ueyang kit method by our team was best,which could extract,higher amount and quality of RNA from the tissues.This method is very suitable for extracting total RNA from XiangS hui Lemon.By using this method,our research team successfully extracted high quality total RNA of white lemon,Guangxi local lemon,kumquat,and mango.

The genetic relationships and genetic diversity of 39 lemon (Citrus limon), lime (C. aurantifolia), and Rangpur (C. limonia) germplasm resources were examined by SCoT and ISSR markers in this study. Of the 80 SCoT primers screened, 9 primers gave reproducible, polymorphic DNA amplification patterns with a total 69 of amplified bands, and the percentage of polymorphic bands was 76.8%. Of the 100 ISSR primers screened, 9 primers gave reproducible, polymorphic DNA amplification patterns with a total 84 of amplified bands, and the percentage of polymorphic bands was 77.4%. UPGMA relationship trees were established based on their similarity coefficients. At the coefficient level of 0.85 for SCoT and 0.77 for ISSR, the 39 germplasm accessions were divided into six groups and five groups, respectively. The application of SCoT and ISSR markers is discussed in this paper.

In this paper, the relationship between floral organ development and the expression of the pair of homologous gene was analysied through detecting the expression level of the pair of homologous gene. Using the Fortunella crassifolia Swingle flowers as the experimental material, we cloned the homologous full-length c DNA sequences of Fc SOC1 gene by the homologous cloning technology. The expression characteristics in different organs of Fortunella crassifolia Swingle were analyzed by real-time fluorescence quantitative PCR. Sequence analysis showed that the c DNA of this pair of homologous genes were 660 bp and 636 bp, encoded 220 and 212 amino acids. They were named Fc SOC1 a and Fc SOC1 b respectively. The similarity of the amino acid sequences between the genes and other Rutaceae plants was more than 90. Real-time fluorescent quantitative PCR indicated that Fc SOC1 a and Fc SOC1 b could express in both vegetative and reproductive organs. The expression levels of Fc SOC1 a and Fc SOC1 b in vegetative organs were different, but they both had a high level expression in flowers,and the expresion rised sharply at the eary stage and later stage of the dev elopment of flower buds. These two genes highly expressed in the stems, leaves, flower bud, inforescences, torus and ovary of flowers. Both Fc SOC1 a and Fc SOC1 b were expressed significantly in flowers, and their expression characteristics indicated that they may play an important role in dominating the growth of flower, and this pair of homologous genes may have gene differentiation because they have different function in the growth of vegetative organs.

A length o f 585 bp F-box gene, named LFB1, was successfully cloned from ‘Xiangshui’lemon tender leaves by RT-PCR methods, which encoded 194 amino acids, the amino acid sequence has F-box structure. Bioinformatics analysis showed that the molecular weight of the protein was 48.94 k D, its isoelectric point was 5.2; Phylogenetic analysis revealed that it clustered with Citrus clementina. q RT-PCR analysis showed that the gene expressed in plant roots, stems, leaves, leaflets, bud, bud, young fruit and mature fruit,The mount of LFB1 gene expression in tissue was: stem>old leaves>root>bud>fruit>mature leaves>young fruit.In the The expression results in different flower organ, indicated that the gene was expressed highest in the stamens, other groups expressed relatively low, the quantity of gene expression in the stamens was about 10 times as much as other organizations. Under adversity stress, the gene expression of the quantity change obviously, the results showed that the gene had a relationship with the pollen germination, growth and environmental stress.

以产于广西的滑皮金柑(滑皮金弹)和长安金柑(融安金柑)幼果和成熟果为试材,采用石蜡切片、扫描电子显微镜显微等技术,对不同发育阶段幼果果皮解剖结构及成熟果皮表皮特征进行观察,统计成熟果实果皮油胞数,并通过气相色谱-质谱联用仪对成熟果皮精油组分进行分析。结果表明,滑皮金柑和融安金柑油胞形成的时间和数量存在明显差异;从两个品种成熟果实果皮精油中共确定了41个组分,萜烯类化合物为主要组分,两个品种均以柠檬烯含量最高;融安金柑果皮精油含量是滑皮金柑的近7倍,滑皮金柑果皮精油组分则更为丰富。

[Objective] The aim was to provide evidence for cultivating main fruit bearing branches of Rongan kumquat,improving its yield and fruit quality.[Method]The correlation among bearing branches length and thickness,leaf number,flowering,fruit setting and fruit characters of Rongan kumquat were investigated and analyzed.[Result] The thickness of the main fruit bearing branches was positive correlated with its length and leaf number.The length,thickness and leaf number of the main fruit bearing branches were positive correlated with the fruit number,and the thickness of the main fruit bearing branch gave the highest impact to the fruit characters.The length of the bearing branches was negative correlated with the apical bud fruit number,the thickness and leaf number were not significantly correlated with that;the length and thickness of the bearing branches and its leaf number were significantly positive correlated with the lateral bud fruit number,especially with the length.[Conclusion] The study has an important significance for cultivating main fruit bearing branches of Rongan kumquat and improving its yield and fruit quality.

Seedlessness is a desirable character in lemons and other citrus species. Seedless fruit can be induced in many ways, including through self-incompatibility (SI). SI is widely used as an intraspecific reproductive barrier that prevents self-fertilization in flowering plants. Although there have been many studies on SI, its mechanism remains unclear. The ‘Xiangshui’ lemon is an important seedless cultivar whose seedlessness has been caused by SI. It is essential to identify genes involved in SI in ‘Xiangshui’ lemon to clarify its molecular mechanism. In this study, candidate genes associated with SI were identified using high-throughput Illumina RNA sequencing (RNA-seq). A total of 61,224 unigenes were obtained (average, 948 bp; N50 of 1,457 bp), among which 47,260 unigenes were annotated by comparison to six public databases (Nr, Nt, Swiss-Prot, KEGG, COG, and GO). Differentially expressed genes were identified by comparing the transcriptomes of no-, self-, and cross-pollinated stigmas with styles of the ‘Xiangshui’ lemon. Several differentially expressed genes that might be associated with SI were identified, such as those involved in pollen tube growth, programmed cell death, signal transduction, and transcription. NADPH oxidase genes associated with apoptosis were highly upregulated in the self-pollinated transcriptome. The expression pattern of 12 genes was analyzed by quantitative real-time polymerase chain reaction. A putative S-RNase gene was identified that had not been previously associated with self-pollen rejection in lemon or citrus. This study provided a transcriptome dataset for further studies of SI and seedless lemon breeding.