Abstract:Based on transcriptome differential expression analysis between the cucumber(Cucumis sativus L.)small-leaf mutant cpa1 and wild type(WT),we found that the expression of the MADS-box transcription factor gene CsAGL62b(CsaV3_3G045410)was significantly downregulated in the cpa1 mutant. The target gene of the cpa1 mutant has been identified as CsHLS1,and its homologous proteins have been shown to play vital regulatory roles in apical hook development and abiotic stress responses in plants.To further dissect the function of CsAGL62b ,the full-length coding sequence of CsAGL62b was cloned from wild-type cucumber using RT-PCR.Bioinformatic analysis showed that this gene encodes a protein of 225 amino acids containing a typical MADS domain.Phylogenetic analysis revealed that it has the closest genetic relationship with CmAGL62b from melon.Promoter cis-element prediction identified regulatory elements associated with light signaling and multiple plant hormones,including methyl jasmonate(MeJA),gibberellin(GA),and salicylic acid.Gene expression pattern analysis indicated that CsAGL62b showed the highest expression level in roots,followed by lateral buds and leaves.Moreover,its transcript abundance was significantly higher in weak roots than in other root types.In the root maturation zone,CsAGL62b expression was significantly induced and upregulated by exogenous GA and abscisic acid(ABA).Meanwhile,CsAGL62b in seedling
leaves responded rapidly to ABA and was upregulated,reaching its peak expression at 6 h of ABA treatment.Stress assays demonstrated that the expression of CsAGL62b exhibited a trend of initial increase followed by decrease under drought,salt,and high-temperature stresses.In contrast,its expression was significantly downregulated under low-temperature stress,suggesting that CsAGL62b may participate in multiple abiotic stress responses in cucumber.In summary,this study systematically characterized the molecular features of the cucumber CsAGL62b gene for the first time,and provides a solid molecular foundation for further elucidating its biological functions in root growth,development,and stress resistance in cucumber.
Abstract:With the aim of screening for tomato germplasm resources resistant to Tuta absoluta,this study utilized 34 tomato accessions and conducted natural infestation with Tuta absoluta adults in a solar greenhouse, at 30 days after inoculation,the number of leaf mines per 100 leaves,fruit infestation rate,and pest index
were systematically investigated.The resistance levels of different tomato germplasm resources to Tuta absoluta were comprehensively evaluated based on the membership function method and cluster analysis.The results showed that none of the tested tomato germplasm resources were completely immune to Tuta absoluta,but significant differences in resistance were observed among the different resources.Among them,the number of mines per 100 leaves of Z2401 and Z2402 was less than 10.00,and both the fruit boring rate and pest index were less than 3.00%.They ranked first and second in the total ranking of membership functions,indicating the strongest insect-resistance.Followed by Z2403,Fanghua 609,Z2405,Z2407 and Z2406,the number of mines per 100 leaves and leaf damage rate were between 10.00-20.00,the fruit infestation rate and pest index ranged
from 5.00% to 13.00% and from 5.00% to 11.00%,respectively,and they ranked third,fourth,fifth,sixth