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41.
This study aimed to investigate the effect of chitin on the antagonistic activity of Rhodosporidium paludigenum against Penicillium expansum, the cause of blue mold in apple fruit, and the possible mechanisms involved. Our results showed that biocontrol efficacy and population growth of R. paludigenum were greatly enhanced when it was harvested from nutrient yeast dextrose with added chitin (NYCB) medium compared with that harvested from nutrient yeast dextrose (NYDB) medium. The ability of R. paludigenum produced in NYCB to induce resistance to blue mold in apple fruit was significantly enhanced. The enhanced disease control efficacy was correlated with higher levels of polyphenoloxidase (PPO) and superoxide dismutase (SOD) activities in apple fruit treated with R. paludigenum. Moreover, the SOD and catalase (CAT) activities of R. paludigenum were stimulated by cultivating in NYCB, while malondialdehyde (MDA) accumulation in the yeast cells was suppressed. These results indicated that adding chitin to normal media might be an effective method to improve the antagonistic activity of R. paludigenum and the active oxygen metabolism of R. paludigenum might be closely related to the biocontrol activity of the yeast. 相似文献
43.
Sowing of chickpea in the heavy‐textured soils of north‐west Bangladesh with minimum tillage technology aims to increase the timely planting of large areas during a relatively short sowing window before soil water deficit limits germination and emergence. However, the seedbed conditions into which chickpea is sown need to be better quantified, so that limiting factors which affect germination and emergence can be identified. Two of the soil physical characteristics of importance are soil water and aeration. Growth cabinet studies have identified the fastest germination and emergence of chickpea on representative soils for this area at gravimetric water contents of 17–18 %, whilst soil water contents above and below this delayed germination and emergence. Emergence was recorded at soil water potentials between field capacity (?10 kPa) and wilting point (?1500 kPa). Emergence was possible at lower soil water potentials in the finer textured soil, whilst in coarser textured soil, emergence was still possible at higher soil water potentials. 相似文献
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Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed. 相似文献
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StudysiteThestudysiteislocatedintheeasternslopeofDaxing'anMountains(47\"25'~49'37'N,119'37'-122\"45'E),whichbelongstotheBalinForestryBu-reauofNeiMenggol.ThemaintopographyislowermountainsandhilIs.Thealtitudeis4oo~1ooom.Theannualaccumulativetemperature(>=1oC)isabout1845oC.AnnuaIprecipitationis42omm.Annualaveragetemperatureis-15t.Thefrost-freeperiodis97d.lnthisarea,thezonalsoilisbrownconiferousforestsoil,theothertypeofsoilismeadowsoilandbogsoiI.ThemainfundamentaIrockisgrinite.ThebasaItisse… 相似文献
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单板层积材用意杨厚单板制造中应注意的几个技术问题 总被引：1，自引：0，他引：1
利用意杨旋切厚单板易使单板背面裂隙度增大。从生产实际出发,对旋切角度参数、旋切安装位置、压尺的使用,以及旋动机磨损以后,如何保证单板层积材用意杨厚单板的旋切质量提出了解决措施。同时指出：为克服意杨厚单板干燥过程中的翘曲变形,宜采用两段干燥工艺。 相似文献