[Objective] Grafting has many advantages, such as increasing yield, improving nutrition and water uptake, and raising resistance to soil-borne diseases and damage caused by biotic or abiotic stressors. It has become a common practice in watermelon. Although the utilization of watermelon grafting has been steadily increasing over time and 95% of commercial watermelon productions actually rely on it in some regions of the world, the higher cost of grafted watermelon transplants is still one of the primary factors limiting application in regions with medium and large-scale production. The labor-efficient automation of grafting has been recognized as a key factor in the wider adoption of grafting. In growing cucurbits, the root-one-cotyledon-removing grafting method is the most commonly used with grafting machines. For root-cutting-one-cotyledon grafting method, root development is an important factor for seedling quality. Because acquiring strong roots is the main purpose for grafting, it is important to understand the root development of grafted seedlings. However, there is little information on the root growth of root-cutting grafted seedlings. In order to apply this grafting technology efficiently, the influence of root-cutting grafting on the root growth and mineral nutrient absorption of watermelon seedlings was studied. [Methods] The watermelon variety Zaojia 84-24 was used as the scion, and the pumpkin variety Zhenzhuang was used as the rootstock. The scion and rootstock seeds were respectively sown into 98-and 72-cell trays with one seed in one cellfilled with mixed seedling substrate (peat moss and pearlite at a volume ratio of 3∶1). The seeds of rootstock and scion were sown on the same day to meet the requirements for grafting experiments. The plants were cultivated in an artificial chamber with a day/night (12 h/12 h) cycle at 28 ℃/18 ℃ with 60%-80% relative humidity. Grafting was performed after the first true leaf developed on the rootstock and scion at 10th day after sowing. When grafting, the seedlings were divided into two groups. One group was grafted using root-cutting-one-cotyledon grafting method (DRC). After grafting, the plants were transplanted into 72-cell tray-plug with mixed seedling substrate. The other group was grafted using one-cotyledon splice grafting method (CK), in that rootstock had intact root system. The grafted seedlings were placed under a plastic film with a day/night cycle at 28 ℃/18 ℃ with more than 90% humidity under low light intensity (75 μmol·m-2·s-1, 12 h/12 h photoperiod) for healing. The grafted plants were exposed to the air 1-3 h per day until the scions were alive and grew. After the healing process, the root growth parameters such as root morphology indexes, root activity and scattered lump rate were measured at 6-day interval. At the same time, samples were also harvested for examining the hormone and mineral contents. [Results] The root diameter of grafted watermelon seedlings with pumpkin root-cutting was thick while the root length, root surface area, root volume, root tip number, root fresh weight and root dry weight were significantly reduced. The scattering lump rate of grafted watermelon seedlings with pumpkin root-cutting was 86.7% while the scattering rate of grafted watermelon seedlings with the control was only 13.3% on the 12th day after grafting. The contents of IAA, CTK and ETH in the root of grafted watermelon seedlings with pumpkin root-cutting significantly increased while the contents of GA and ABA significantly decreased. The contents of N, P, K, Mg, Fe and B in stems and roots of grafted watermelon seedlings with pumpkin root-cutting showing a certain degree of increase. However, the contents of Ca in stems and roots of grafted watermelon seedlings with pumpkin root-cutting decreased significantly. [Conclusion] A well-developed root system induced vigorous stem growth and plant development, and root growth was also influenced by stem. The root of watermelon seedlings grafted by root-cutting grafting method was regenerated with adventitious roots. The regenerated root system had higher root activity and mineral absorption capacity. The contents of N, P, K, Fe, Mg and B increased in grafted watermelon seedlings with pumpkin root-cutting. At the same time, the seedlings increased the IAA, CTK and ETH contents of root to promote the root growth. However, the seedlings by using this grafting method had not enough root system at the early stage, which decreased the accumulation of mineral elements. The content of Ca was reduced in grafted watermelon seedlings with pumpkin root-cutting, which may be related to the difference in root architecture, but further research is needed to understand the decrease of Ca absorption. The results of this study can provide theoretical guidance for the fertilizer management of watermelon grafting seedlings, and promote the popularization and application of mechanized grafting technology.

Graft healing is a complex process affected by environmental factors, with temperature being one of the most important influencing factors. Here, oriental melon grafted onto pumpkin was used to study changes in graft union formation and sugar contents at the graft interface under night temperatures of 18 °C and 28 °C. Histological analysis suggested that callus formation occurred 3 days after grafting with a night temperature of 28 °C, which was one day earlier than with a night temperature of 18 °C. Vascular reconnection with a night temperature of 28 °C was established 2 days earlier than with a night temperature of 18 °C. Additionally, nine sugars were significantly enriched in the graft union, with the contents of sucrose, trehalose, raffinose, D–glucose, D–fructose, D–galactose, and inositol initially increasing but then decreasing. Furthermore, we also found that exogenous glucose and fructose application promotes vascular reconnection. However, exogenous sucrose application did not promote vascular reconnection. Taken together, our results reveal that elevated temperatures improve the process of graft union formation through increasing the contents of sugars. This study provides information to develop strategies for improving grafting efficiency under low temperatures.

武汉夏秋育苗,温度高、苗期短,易出现种苗徒长、烧苗、脱肥、病虫害大规模频发等问题.结合种植季节和种苗习性,介绍了武汉地区夏秋瓜菜类育苗关键技术,包括选择品种、育苗场地选择、播种、苗期管理和培育壮苗等方面.

为筛选出对温室草莓红蜘蛛具有较好防治效果的杀螨剂,对3种常用药剂及其与1种具杀螨作用的微生物菌剂混配进行药效比较试验.试验结果表明,阿维菌素和联苯肼酯的综合防效表现较好;菌剂与杀螨剂混配以螺螨酯的综合防效表现较佳,显著提高螺螨酯的防效.建议生产中草莓红蜘蛛防治优先使用阿维菌素、联苯肼酯,其次为菌剂与螺螨酯混配.

The rising age of the population in rural China and the labor intensity of grafting have resulted in a decrease in the number of grafters and a subsequent increase in their wages. Manual grafting can no longer satisfy the increasing demand for watermelon-grafted transplanting; thus, machine grafting will be an effective alternative. In order to accelerate the implementation of machine grafting in China, a comparative analysis between the automatic grafting machine (model 2TJGQ-800) and traditional hand grafting was conducted. The reliability and feasibility of machine grafting were evaluated through a comprehensive evaluation of the production capacity and grafting seedling quality. This study focuses on the grafting application of watermelon plug-tray seedlings. The scion and rootstock seeds were sown on 9 November 2022. Grafting experiments using an automatic grafting machine, skilled workers, and ordinary workers were conducted with the root-pruned one-cotyledon grafting method on 24 November 2022. The results showed that the machine grafting had a high uniformity and grafting speed. The grafting speed of the grafting machine was 774 plant·h−1 and 1.65–2.55-fold higher than the hand grafting. With training, workers can improve their grafting speed, but it will still be slower than machine grafting. In addition, there was no significant difference in the grafting survival rate between the machine grafting and hand grafting. However, using machine grafting, the success rate decreased from 100% to 90.07% and the rootstock regrowth rate increased from 18.44% to 72.69%. Incomplete rootstock cutting, clip supply failure, and grafting drop failure are the three main factors that result in machine grafting failure. In conclusion, the grafting machine has advantages in terms of grafting speed and uniformity. Upon improving the accuracy of the cutting mechanism and grafting success rate, it will be adopted by commercial nurseries.

导读:为了优化瓜菜栽培模式,充分利用有效大棚资源,创造出更大的经济效益,经过不断摸索和实践,形成了一套适于武汉地区大棚西瓜—哈密瓜—松花菜轮作高效栽培模式.

The labor-efficient automation of grafting has been recognized as a key factor in the wider adoption of grafting. In growing cucurbits, the root pruned one-cotyledon grafting method is the most commonly used method with grafting machines. The cutting angle, which affects the matching of the rootstock and scion, is key to the survival of the graft seedling. In the production of cucurbit graft seedlings, the cutting parameters are established based on experience, leading to low grafting success. To determine accurate cutting parameters, the watermelon cv. ‘Zaojia84-24′ was used as the scion and the pumpkin cv. ‘Zhenzhuang’ was used as rootstock, and two one-way experiments investigating the cutting angle of the watermelon scion and the rootstock as factors were conducted. The cutting angle of the rootstock and scion had no significant effect on the xylem reconnection rate or the grafting survival rate. A larger cutting angle for the rootstock and scion led to a delay in the reconnection of the phloem. Different cutting angles for the scion significantly affected the growth of the scion after grafting. Compared with a scion graft cutting angle of 10° (SL), graft cutting angles of 14° (SM) and 20° (SS) led to significantly greater scion dry weights, with increases of 16.00% and 18.61%, respectively. Different cutting angles of the rootstock significantly affected the growth of roots after grafting. Compared with a rootstock graft cutting angle of 10° (RL), graft cutting angles of 17° (RM) and 27° (RS) led to significantly greater root dry weights, with increases of 29.33% and 22.54%, respectively. The results of this study can provide a reference for the design of cutting mechanisms for cucurbit grafting robots, improving the cutting precision of grafting robots.

Damping-off caused by Pythium aphanidermatum (Pa) is one of the most destructive diseases for watermelon seedlings. Application of biological control agents against Pa has attracted the attention of many researchers for a long time. In this study, the actinomycetous isolate JKTJ-3 with strong and broad-spectrum antifungal activity was screened from 23 bacterial isolates. Based on the morphological, cultural, physiological, and biochemical characteristics as well as the feature of 16S rDNA sequence, isolate JKTJ-3 was identified as Streptomyces murinus. We investigated the biocontrol efficacy of isolate JKTJ-3 and its metabolites. The results revealed that seed and substrate treatments with JKTJ-3 cultures showed a significant inhibitory effect on watermelon damping-off disease. Seed treatment with the JKTJ-3 cultural filtrates (CF) displayed higher control efficacy compared to the fermentation cultures (FC). Treatment of the seeding substrate with the wheat grain cultures (WGC) of JKTJ-3 exhibited better control efficacy than that of the seeding substrate with the JKTJ-3 CF. Moreover, the JKTJ-3 WGC showed the preventive effect on suppression of the disease, and the efficacy increased with increase in the inoculation interval between the WGC and Pa. Production of the antifungal metabolite actinomycin D by isolate JKTJ-3 and cell-wall-degrading enzymes such as β-1,3-glucanase and chitosanase were probably the mechanisms for effective control of watermelon damping-off. It was shown for the first time that S. murinus can produce anti-oomycete substances including chitinase and actinomycin D. This is the first report about S. murinus used as biocontrol agent against watermelon damping-off caused by Pa.

Fannia canicularis (Linnaeus, 1761) is a species from the family Fanniidae. In this study, we sequenced and analyzed the complete mitochondrial genome of F. canicularis for the first time. The circular mitogenome is 15,826 bp in length, and includes 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and a non-coding control region. The family Fanniidae formed a monophyletic clade in the phylogenetic tree based on 13 concatenated PCGs, sister to three other families in Diptera.

我国是全球西甜瓜生产与消费第一大国,西甜瓜播种面积超过200 万hm2,占蔬菜播种面积的10％以上,西甜瓜在我国农业结构调整与农民增收中发挥着重要作用.武汉市的西甜瓜生产源远流长,曾被列入武汉市"十大"优势农产品之一.20世纪70年代前后,洪山天兴洲、江夏土地堂、汉阳拦江堤的西甜瓜曾响誉江城,久负盛名."西瓜王,土地堂",唤起几代江城人的儿时记忆.

甜瓜(Cucumis melo L.)不同亚种和品种对生态条件的要求不同,哈密瓜作为一种厚皮甜瓜,适于高温、干燥、昼夜温差大、日照充足的气象条件[1,2].武汉地处长江中下游地区,秋季(9月初至10月中旬)天气变化过程大体可分为秋高气爽、秋风秋雨以及随之出现的低温寒露天气[3].9月秋高气爽、光照充足、昼夜温差大的独特气候优势特别适宜发展哈密瓜栽培.近年来,武汉秋季栽培哈密瓜中心糖可以达到17°～19°,品质好,口感脆甜.另外,武汉秋季哈密瓜可在9月下旬至10月中旬上市,避开新疆等西北地区哈密瓜7～9月上市的高峰期,抢在海南等华南地区秋延后哈密瓜上市之前,弥补新疆哈密瓜和海南哈密瓜首尾不接的空档[4].因此,在武汉发展秋季哈密瓜种植具有广阔的前景.

以西瓜品种早佳84-24为接穗,南瓜品种砧壮为砧木,研究不同砧/穗苗龄对机器嫁接苗生长发育的影响.结果表明,砧/穗苗龄显著影响嫁接苗成活质量和生根,其中,影响嫁接成活率、嫁接苗侧根数、根长度和根体积等的主要因素是砧木苗龄,影响叶片健全指数的主要因素是接穗苗龄,心叶绝对生长速率受砧/穗苗龄的共同影响,但无显著相关性.采用满意度综合评价确定适宜机械化贴接的砧木苗龄为16 d,即第1片真叶1角硬币大小,茎粗3.20±0.16 mm;接穗苗龄为16～19 d,即第1片真叶露心到一叶一心期,茎粗2.76±0.23 mm.

为快速有效地减轻百日草(Zinnia elegans Jacq.)种苗生产中因徒长而导致的植株倒伏、弯曲以及商品性降低、抗性减弱的问题,本研究选用3种株型调控剂,即丁酰肼(B9)、烯效唑(S3307)和多效唑(PP333),与种衣剂混配后对种子进行包衣处理,调查百日草的植物性状.结果表明:3种不同浓度的株型调控剂处理后,均有降低种苗高度、缩短节间与增加茎粗、提升种苗质量的作用.其中50 mL·L-1种衣剂+40 g·L-1 PP333处理效果最显著,株高、第1节间、下胚轴分别比对照降低了40.1％、52.4％ 和63.0％,茎粗、壮苗指数、根冠比增加了7.4％、79.2％ 和29.6％.说明3种株型调控剂中40 g·L-1 PP333对百日草矮化效果最优,较适宜与种衣剂混合对百日草进行包衣处理.

育苗是蔬菜生产重要环节,近年来我国蔬菜育苗技术取得显著进展.本文系统总结了"十三五"期间我国蔬菜育苗在种子处理、基质生产、生长发育调控、嫁接等方面取得的重要进展,分析了存在的主要问题,探讨了未来的发展方向.

草莓营养丰富、种植经济效益高,近几年在武汉地区发展迅猛.对武汉地区草莓产业的栽培、育苗、育种等现状进行了分析,发现存在技术水平参差不齐、品种相对简单、栽培方式保守、种苗质量不稳定、产业链延伸不够等问题,并有针对性地提出了相关建议.

基于设施蔬菜在蔬菜产业中的主导地位,分析武汉设施蔬菜生产现状、尾菜资源化利用现状及存在的问题,并提出加强宣传、建立尾菜资源化利用技术体系、制订扶持政策、建立长效机制的发展对策,为有效开展设施蔬菜尾菜资源化利用提供参考.

育苗始终是蔬菜栽培的重要环节,种苗质量直接影响蔬菜产量和品质.21世纪前10 a(年),在武汉市政府相关部门的支持下工厂化育苗产业得到快速发展.然而,近年来工厂化育苗表现相对滞后,产业面临诸多问题.笔者总结了武汉市工厂化育苗产业的发展特点,针对存在的设备不完善,生产成本高,科技研发能力不足,种苗质量不稳定等问题,提出政府统筹规划、降低生产成本、加强科技创新以及完善种苗行业标准等措施,旨在为更好推动武汉市工厂化育苗产业健康发展提供借鉴.

为了探讨基质中适宜的保水剂添加量,以砧木葫芦为材料,研究了保水剂不同添加量处理对基质理化性状和葫芦幼苗生长发育的影响.结果表明,随着保水剂添加量的增加,基质的pH值和EC值呈逐渐升高趋势,通气孔隙和容重呈逐渐降低趋势,总孔隙和持水孔隙以及葫芦幼苗株高、全株干质量、叶面积、主根长、根体积和壮苗指数均呈先升高后降低趋势.保水剂添加量(ρ,后同)为1.0 g?L-1时,基质的理化性状在正常范围内,葫芦幼苗的根干质量、根体积、叶面积和壮苗指数分别比对照提高了7.01％、41.67％、41.88％和21.4％,促进幼苗生长,提高幼苗质量.综合考虑基质理化性状、幼苗长势和经济因素,建议保水剂的添加量为1.0 g?L-1.

为解决辣椒工厂化穴盘育苗容易徒长的问题,以湖湘贵妃辣椒为试材,研究不同浓度多效唑、烯效唑和烯唑醇对辣椒穴盘苗生长发育的影响.试验结果表明,多效唑、烯效唑、烯唑醇对辣椒穴盘苗生长有显著的抑制作用,其中,200 mg/L烯唑醇处理的辣椒穴盘苗的株高、茎粗、地上部干质量、地下部干质量和生长函数G值的降低幅度最大,根冠比和壮苗指数的增加幅度最大,初步得出烯唑醇可作为一种化学调控剂调控辣椒穴盘苗株型,其中以浓度200 mg/L处理的效果较好.

In this study, we sequenced and analyzed the complete mitochondrial genome of Mansonia uniformis, and this is the first report on the genus Mansonia. The circular mitogenome is 15,603 bp long and contains 13 protein-coding genes (PCGs), 22 tRNA genes, 2 ribosomal RNA genes, and a A + T-rich control region. Most PCGs start with ATN codons, and end with TAA, except for COX1 starting with TCG codons and COX2 ending with a single thymine stop codon. The phylogenetic tree based on the COX1 gene showed that M. uniformis formed a monophyletic clade, sister to other seven genus from the subfamily Culicinae.