Shu’an Wang, Rutong Yang, Peng Wang, Qing Wang, Linfang Li, Ya Li and Zengfang Yin
Yinping Shi, Qiangsheng Wang, Jianming Yang, Congyi Sui and Qingrong Sun
To perform apple polyploid breeding the ways of inducing polyploidy pollen with temperature and chemicals were studied. Materials include 13 diploid cultivars: Red Chief, Dai Hong, Rose Red, Golden Delicious, Mollie's Delicious, Gala, Bella, Jonathan, Fuji, Qiu Kou Hong, and Yan Qing, OBIR-2T-47. Chemicals: Chloroform, N-nitroso-ethylurea. At the beginning of PMC meiosis, fruiting branching groups were covered with plastic bags to raise temperature or were treated with chemical. After covering, temperature during the day increased 2 °C, generally not lower than 0 °C. Whether branches received high temperature or chemicals treatment, polyploidy pollen was induced to produce. The pollen grain of CK is tricolporat, its polar view is triangular, and its diameter almost 40 μm, showing no difference in size. Rate of empty pollen grain is low. Pollen grains that were treated were different in size, and rate of empty pollen is high, part of pollen grains germinating colporat change into tetracolporat with a few polycolporat, its polar view is square, round, and oval. The diameter of large pollen grains was 45-48 μm, increased by 11-12%. Giant pollen grain are 50-68 μm, increased by 25%-70%. Rate of induction is different in different cultivars. For most cultivars, giant pollen grain is 0.3%-0.5%. Gala and OBIR-2T-47 were higher, reaching 2.5%-7%. Chemicals caused damage on cultivars. Delicious strains were easily damaged.
Yau-Wen Yang, Ching-Chang Tsai and Tsu-Tsuen Wang
Rangjian Qiu, Yuanshu Jing, Chunwei Liu, Zaiqiang Yang and Zhenchang Wang
It has been proved that irrigation with high saline water and leaching fraction (LF) affect crop yield, but the effects of irrigation water salinity (ECiw) and LF on fruit quality remain largely elusive. We therefore investigated the effects of ECiw and LF on the yield, fruit quality, and ion content of hot peppers. An experiment using irrigation water with five levels of salinity (ECiw of 0.9, 1.6, 2.7, 4.7, and 7.0 dS·m−1) and two LFs (0.17 and 0.29) was conducted in a rain shelter. The experiment took the form of a completely randomized block design, and each treatment was replicated four times. We increased the salinity of the irrigation water by adding 1:1 milliequivalent concentrations of NaCl and CaCl2 to a half-strength Hoagland solution. The plants were irrigated for 120% and 140% evapotranspiration, corresponding to an LF of 0.17 and 0.29. Results showed that the total fruit yield decreased significantly with an increase in the ECiw as a result of reduction both in the fresh weight of fruit and the number of fruit per plant. An increase in the ECiw also led to a decrease in the total dry biomass of fruit and plant, as well as decreasing water use efficiency (WUEF). Salinity reduced the appearance of the fruit by both decreasing the length (FL) and maximum width (FMW) of the fruit. However, increased ECiw also improved the taste of the hot peppers by increasing the total soluble solid (TSS) content, as well as adding to their nutritional quality with a higher content of Vitamin C (VC). Their storage quality was also improved because of an improvement in the firmness of the fruit (Fn) as well as a reduction in the fruit water content (FWC). An increase in the LF led to an increase in the total fruit yield, total dry biomass of fruit and plant, and WUEF; it also increased the FWC and VC content, and decreased the FMW and fruit shape index (FSI). The threshold-slope linear response and sigmoidal-sharp models were both a good fit for the measured total fruit yield, and the LF had no significant effect on the model parameters. The relative TSS and Fn increased linearly as the electrical conductivity (EC) of soil-saturated paste extract (ECe) increased, whereas they decreased linearly as the relative seasonal evapotranspiration (ETr) increased regardless of the LFs. The relative FW, FL, and FMW decreased linearly with the increased ECe, and increased linearly with the increased ETr regardless of the LFs. The relative fruit Na+ concentration increased linearly as the ECe increased. The regression correlations between the total fruit yield, fruit quality parameters, ion contents, and ECe or ETr could provide important information for salinity and irrigation water management with a compromise between the hot pepper yield and fruit quality.
Luping Qu, Xiping Wang, Jinghua Yang, Eatherley Hood and Richard Scalzo
Seeds from five lots each of Echinacea angustifolia DC and E. pallida (Nutt.) Nutt. were germinated in a growth chamber in light (40 μmol·m-2·s-1) or darkness at 25 °C for 16 to 20 days after soaking in 1 mm ethephon or water for 10 minutes or moist stratification at 4 - 6 °C for 2 weeks. Either light or ethephon promoted seed germination of E. angustifolia and E. pallida compared with darkness in nine of ten lots. Ethephon in the dark had similar or greater germination percentages than water with light. Ethephon with light improved germination in three of ten lots compared with ethephon in the dark. The effect of cold, moist stratification compared with darkness varied by seed lot. Five lots of E. purpurea (L.) Moench were tested, however, no treatment differences were measured. The finding that ethethon promoted E. angustifolia and E. pallida seed germination in darkness could be useful in the cultivation of these two species. Chemical name used: 2-chloroethylphosphonic acid (ethephon).
Xinyi Zhang, Li Liao, Yang Liu, Zhiyong Wang and Jianxiu Liu
Chrysopogon aciculatus (Retz.) Trin. is a perennial turfgrass for its low management and resistance. To develop simple sequence repeat (SSR) markers for C. aciculatus, we used four Roche 454 pyrosequencing, combined with the magnetic bead enrichment method FIASCO (fast isolation by amplified fragment length polymorphism of sequences containing repeats) to isolate from the C. aciculatus. A total of 66,198 raw sequencing reads were obtained with 4289 sequences (6.48%) were fit for primer pair design. One hundred microsatellite loci were selected to test the primer amplification efficiency in 20 accessions, and out of these, 11 loci were polymorphic. The amount of observed alleles ranged from three to six, with an average of 3.64. Nei’s genetic diversity values ranged from 0.085 to 0.493, with an average of 0.293. Shannon’s information index values ranged from 0.141 to 0.686, with an average of 0.428. Twenty accessions were clustered into three groups by unweighted pair-group method with arithmetic means (UPGMA). These SSR markers will provide an ideal marker system to assist with gene targeting, cultivar variety or species identification, and marker-assisted selection in C. aciculatus species.
Supriyo Basak, Guangyan Wang, Xudong Sun and Yongping Yang
Brassica rapa var. rapa (turnip) is considered a main source of food for the inhabitants of the Qinghai-Tibetan Plateau (QTP) and its adjacent highlands when other crops are scarce. The QTP ranges from lat. 25.59°N to 39.49°N and from long. 73.29°E to 104.40°E, whereas the Yunnan Plateau ranges from lat. 20.00°N to 29.16°N and from long. 96.00°E to 110.19°E. A comparison between the turnip landraces of two different plateau environments can provide a mechanistic insight into plant adaptation in highlands. The aim of this investigation was to understand the patterns in variation in genome size (GS) between the turnip landraces of two plateau environments. We used a well-established protocol to count chromosome number and performed propidium iodide flow cytometry to measure GS. No polyploidy was detected among the turnip landraces tested, and 15.5% variation in GS was observed between the landraces. No consistent pattern pertaining to GS variation emerged after the environmental variables were considered. Thus, we propose that such pattern may reflect the indirect effect of selection, random process, genetic drift, or some other factors on GS through interaction of life-form and phenotypic traits.
Hua Gao, Zheng-yang Zhao, Lei-cun Wang, Zhen-zhong Liu and Ya-zhou Yang
Liu Yang, Zhongkui Xie, Zhijiang Wu, Yajun Wang, Zhihong Guo, Yubao Zhang and Ruoyu Wang
The oriental hybrid lily (Lilium oriental cv. Sorbonne) is an economically important flower noted for its pink petals. Flower quality is determined by plant height, number of flowers per plant, and flower diameter. The commercial value can be increased by improving flower quality through cultural practices such as exogenous application of hormones; however, information on this practice is unavailable for this lily hybrid. In the present study, we soaked lily bulbs for 24 hours in one of four concentrations of abscisic acid (ABA) or one of three concentrations of the ABA biosynthesis inhibitor fluridone before subjecting the bulbs to a cold storage treatment at 4 °C. During cold storage, bulbs were sampled and buds were collected every 10 days for 80 days (that is, lasting eight times). The ABA and gibberellic acid 3 (GA3) contents of buds of treatments that showed a significant difference with the control were measured in a 10-day interval. Greenhouse experiments with different cold storage durations of bulbs that measured height, flower number per plant, and flower diameter were conducted. The interaction of hormone treatments and cold storage duration played nonsignificant roles in parameters of flower quality. Exogenous fluridone application to bulbs at 12 mg·L−1 improved flower quality: height and flower number increased significantly compared with the control, but flower diameter did not change. ABA had no effect on flower quality. Because the fluctuation of endogenous GA3 is more remarkable than ABA after the application of fluridone that led to the improvement of flower quality, it can be inferred that this influence on flower quality is achieved through fluridone’s regulation on the content of endogenous GA3. A low endogenous GA3/ABA ratio was associated with improved flower quality: 12 mg·L−1 fluridone decreased the GA3/ABA ratio in most times of the cold treatment. In addition, cold storage duration affected flower quality; the 50-day cold storage can achieve the highest height, the most flower number, and bigger flower diameter simultaneously. The results of the present study suggest that soaking bulbs in 12 mg·L−1 fluridone before cold treatment followed by 50 days of cold storage before planting will increase plant height and flower number per plant.
Yu Bai, Ying Zhou, Xiaoqing Tang, Yu Wang, Fangquan Wang and Jie Yang
The appropriate timing of bolting and flowering is one of the keys to the reproductive success of Isatis indigotica. Several flowering regulatory pathways have been reported in plant species, but we know little about flowering regulatory in I. indigotica. In the present study, we performed RNA-seq and annotated I. indigotica transcriptome using RNA from five tissues (leaves, roots, flowers, fruit, and stems). Illumina sequencing generated 149,907,857 high-quality clean reads and 124,508 unigenes were assembled from the sequenced reads. Of these unigenes, 88,064 were functionally annotated by BLAST searches against the public protein databases. Functional classification and annotation assigned 55,991 and 23,072 unigenes to 52 gene ontology (GO) terms and 25 clusters of orthologous group (COG) categories, respectively. A total of 19,927 unigenes were assigned to 124 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and 80 candidate genes related to plant circadian rhythm were identified. We also identified a number of differentially expressed genes (DEG) and 91 potential bolting and flowering-related genes from the RNA-seq data. This study is the first to identify bolting and flowering-related genes based on transcriptome sequencing and assembly in I. indigotica. The results provide foundations for the exploration of flowering pathways in I. indigotica and investigations of the molecular mechanisms of bolting and flowering in Brassicaceae plants.