Genome-wide analysis of the AINTEGUMENTA-like (AIL) transcription factor gene family in pumpkin (Cucurbita moschata Duch.) and CmoANT1.2 response in graft union healing.

AINTEGUMENTA-like (AIL) proteins are members of the APETALA 2/ETHYLENE RESPONSE FACTOR (AP2/ERF) domain family of transcription factors involved in plant growth, development, and abiotic stress responses. However, the biological functions of AIL members in pumpkin (Cucurbita moschata Duch.) remain unknown. In this study, we identified 12 AIL genes in the pumpkin genome encoding proteins predicted to be localized in the nucleus. Phylogenetic analysis showed that the AIL gene family could be classified into six major subfamilies, with each member encoding two AP2/ERF domains separated by a linker region. CmoAIL genes were expressed at varying levels in the examined tissues, and CmoANT genes showed different expression patterns under auxin (IAA), 1-naphthylphthalamic acid (NPA), and abscisic acid (ABA) treatments. Ectopic overexpression of CmoANT1.2 in Arabidopsis increased organ size and promoted growth of grafted plants by accelerating graft union formation. However, there was no significant difference at the graft junction for WT/WT and WT/ANT under IAA or NPA treatments. Taken together, the results of this study provide critical information about CmoAIL genes and their encoded proteins, and suggest future work should investigate the functions of CmoANT1.2 in the grafting process in pumpkin.

[Effects of vegetable residue compost returning to soil on soil properties and vegetable yield in solar greenhouse.] / æ—¥å ‰æ¸©å®¤è”¬èœæ®‹æ ªå †è åŽè¿˜ç”°å¯¹æ ¹åŒºåœŸå£¤çŽ¯å¢ƒåŠè”¬èœäº§é‡çš„å½±å“.

In order to explore reasonable utilization of vegetable residue, the effects of application of different levels (0, 15, 20, 30 t·hm-2) of tomato and cucumber residue compost on soil pro-perties, the leaf photosynthesis and the yield of vegetables were studied in solar greenhouse. The results showed that both kinds of vegetable compost could reduce soil bulk density, increase soil organic matter content, soil microbial biomass and soil enzyme activity, promote plant growth, and improve vegetable yield and quality. The more amount compost returned, the better was the effect on plant growth and yield. The positive effect of the vegetable residue compost application in the second cucumber growing season was more noticeable than that in the first tomato growing season, which indicated the application of vegetable residue compost could effectively promote soil fertility, increase vegetable yield and improve vegetable nutrient quality.

[Effects of different NO3--N/NH4+-N ratios on cucumber seedlings growth, nitrogen absorption and metabolism under suboptimal temperature and light intensity]. / äºšé€‚å®œæ¸©å ‰çŽ¯å¢ƒä¸‹ä¸åŒç¡é“µæ¯”è¥å »æ¶²å¯¹é»„ç“œå¹¼è‹—ç”Ÿé•¿ã€æ°®å¸æ”¶å’Œä»£è°¢çš„å½±å“.

Cucumber (cv. Zhongnong 26) was used as material, the effects of NO3--N/NH4+-N ratios on growth and physiological characteristics of cucumber seedlings under suboptimal temperature and light intensity (18 ℃/10 ℃,180 ± 20 µmol·m-2·s-1) were studied. Total nitrogen in the nutrient solution was equal and three NO3--N/NH4+-N ratios, 26:2, 21:7 and 14:14, were applied as treatments. The results showed that cucumber treated by NO3--N/NH4+-N=21:7 had the longest total root length, the biggest root volume and root surface area, and the maximum number of root tips. H+-ATPase activity and relative expression of genes encoding nitrate transporter (NRT) and ammonium transporter (AMT) in cucumber roots were increased significantly by the treatment of NO3--N/NH4+-N=21:7. In addition, nitrate reductase (NR), glutamine synthetase (GS) and glutamate synthase (GOGAT) in cucumber leaves under the treatment of NO3--N/NH4+-N=21:7 were higher. As a result, the nitrogen content and biomass of cucumber were significantly increased. Compared with the plants under the treatment of NO3--N/NH4+-N=26:2 or 14:14, cucumber seedlings under the treatment of NO3--N/NH4+-N=21:7 had the highest biomass and total dry mass (DM) which were increased by 14.0% and 19.3% respectively under suboptimal temperature and light intensity. In conclusion, under suboptimal environmental conditions, NO3- -N/NH4+-N ratio could be adjusted to increase nitrogen absorption and metabolism of cucumber and alleviate the de-trimental effects caused by suboptimal conditions and promoted the cucumber growth.

[Effects of sodium naphthalene acetate on growth and physiological characteristics of tomato seedlings under suboptimal temperature and light condition].

Taking tomato 'Zhongza 105' as test material, the influences of sodium naphthalene acetate (SNA) on growth and physiological characteristics of tomato seedlings under suboptimal temperature and light condition were investigated. The results showed that the dry mass, vigorous seedling index, root activity, total nitrogen content, net photosynthesis rate (Pn) of tomato seedlings were significantly decreased by suboptimum temperature and light treatment. In addition, the catalase activity and zeatin riboside (ZR) concentration were also reduced. However, the superoxide dismutase, peroxidase activity and the content of abscisic acid (ABA) were increased. Compared with treatment of the same volume distilled water on tomato seedlings under suboptimum temperature and light condition, the dry mass of whole plant and vigorous seedling index of tomato seedlings were significantly increased by 16.4% and 22.9%, as the total N contents in roots and leaves and Pn were also increased by 8.5%, 28.5%and 37.0%, respectively, with the treatment of root application of 10 mg . L-1 SNA. Besides protective enzyme activity and the root activity were improved, the indole acetic acid (IAA) and ZR concentration of tomato were raised, and ABA concentration was reduced. The results indicated that root application of certain concentration of SNA could promote the growth of tomato seedlings by increasing the tomato root activity, protective enzymes activity, Pn and regulating endogenous hormone concentration under suboptimum temperature and light condition.

[Changes of organic soil substrate properties with different cultivation years and their effects on cucumber growth in solar greenhouse].

This paper studied the changes of organic soil substrate properties with increasing cultivation years and their effects on the cucumber growth in solar greenhouse. The results showed that with increasing cultivation years, the physical and chemical properties of organic soil substrate deteriorated, which was manifested in the increase of bulk density and the decrease of total porosity, pH, and available nutrient contents. The numbers of bacteria and actinomycetes in the substrate decreased with increasing cultivation years, while that of fungi was in reverse. The cucumber growth was also affected to a certain extent, manifesting in the decrease of plant height and leaf area, the decline of photosynthetic efficiency, and the decrease of yield and quality. It would be necessary to restore the fertility of organic soil substrate after 3-year cultivation.

[Mathematic models of cucumber net photosynthesis rate responding to CO2 concentration, temperature, and illumination intensity].

With two cucumber varieties (greenhouse variety Jinyou No. 1 and open-field variety Jinyan No. 4) as test materials, this paper measured their net photosynthesis rate (P(n)) under given environmental conditions including CO2 concentration, temperature and illumination intensity in phytotron, and the responses of P(n) (y) to these factors were modeled by mathematic methods, which could be described as y = exp (- 242. 1217/x1) [61.0202 - 0.11 (x2 - 30.926)2] exp (-272. 8874/x3) + 0.9355 for Jinyou No. 1, and y = exp (- 179.8803/x1) [50.0771-0.0609 (x2 -34.3455)2] exp (-267.9653/x3) + 0.7377 for Jinyan No. 4, where x1, x2 and x3 represented the values of CO2 concentration, temperature, and illumination intensity, respectively. The response of P(n) to temperature accorded with conic function, while its responses to CO2 concentration and illumination intensity accorded with exponential function.