ABSTRACT
Objective To evaluate the molluscicidal activity of surfactin against Oncomelania hupensis, so as to provide the experimental basis for use of Bacillus for killing O. hupensis. Methods O. hupensis snails were collected from schistosomiasisendemic foci of Wuhu City on September 2022, and Schistosoma japonicum-infected snails were removed. Then, 60 snails were immersed in surfactin at concentrations of 2, 1, 0.5, 0.25, 0.125 mg/mL and 0.062 5 mg/mL for 24, 48, 72 hours at 26 °C, while ultrapure water-treated snails served as controls. The median lethal concentration (LC50) of surfactin against O. hupensis snails was estimated. O. hupensis snails were immersed in surfactin at a concentration of 24 h LC50 and ultrapure water, and then stained with propidium iodide (PI). The PI uptake in haemocyte was observed in O. hupensis snails using fluorescence microscopy. Results The mortality of O. hupensis was 5.0% following immersion in surfactin at a concentration of 0.062 5 mg/mL for 24 h, and the mortality was 100.0% following immersion in surfactin at a concentration of 2 mg/mL for 72 h, while no snail mortality was observed in the control group. There were significant differences in the mortality of O. hupensis in each surfactin treatment groups at 24 (χ2 = 180.150, P < 0.05), 48 h (χ2 = 176.786, P < 0.05) and 72 h (χ2 = 216.487, P < 0.05), respectively. The average mortality rates of O. hupensis were 38.9% (140/360), 62.2% (224/360) and 83.3% (300/360) 24, 48 h and 72 h post-immersion in surfactin, respectively (χ2 = 150.264, P < 0.05), and the 24, 48 h and 72 h LC50 values of surfactin were 0.591, 0.191 mg/mL and 0.054 mg/mL against O. hupensis snails. Fluorescence microscopy showed more numbers of haemocytes with PI uptake in 0.5 mg/mL surfactintreated O. hupensis snails than in ultrapure water-treated snails for 24 h, and there was a significant difference in the proportion of PI uptake in haemocytes between surfactin-and ultrapure water-treated snails (χ2 = 6.690, P < 0.05). Conclusion Surfactin is active against O. hupensis snails, which may be associated with the alteration in the integrity of haemocyte membrane.
ABSTRACT
<p><b>OBJECTIVE</b>To study the salt stress tolerance of Hongxinju, Huangju and F1 seedlings from orthogonal and reciprocal cross under different salt treatments. Grope for transmissibility of salt tolerance between parents and F1 seedlings, and relativity between flavone, chlorogenic acid contents and salt tolerance.</p><p><b>METHOD</b>The materials were put in 5 different concentrations of Hoagland nutrient solution (0, 40, 80, 120, 160 mmol x L(-1)) containing NaCl, keeping grads while raising the consistency of NaCl day by day. The injured leaf area per plant, proline, betaine, MDA, flavones and chlorogenic acid contents were measured and analyzed after treatment.</p><p><b>RESULT</b>As NaCl concentration was below 120 mmol x L(-1), the salt tolerance of Hongxinju was higher than that of Huangju, the salt tolerance of Hongxinju x Huangju higher than that of parents, the salt tolerance of Huangju x Hongxinju was at the level of parents. As NaCl concentration between 120 to 160 mmol x L(-1), the salt tolerance of Huangju was higher than that of Hongxinju, the salt tolerance of Huangju x Hongxinju higher than that of parents and the salt tolerance of Hongxinju x Huangju was at the level of parents.</p><p><b>CONCLUSION</b>Salt tolerance of F1 is more influenced by female parent, relativity showed between flavonoids, chlorogenic acid contents and salt tolerance.</p>
Subject(s)
Breeding , China , Chlorides , Metabolism , Chrysanthemum , Genetics , Physiology , Salt Tolerance , Seedlings , Genetics , PhysiologyABSTRACT
Objective To seek the optimization hormone combination for the callus induction and differentiation from cotyledon and hypocotyl explants of Chrysanthemum morifolium through tissue culture. Methods Cotyledon and hypocotyl explants were cultured on various medium with different hormone combinations. Results Callus could be inducted on every media designed in this experiment,but the effects to the induction and differentiation culture of buds were different.The results showed that the medium MS+IAA 0.3 mg/L+6-BA 12 mg/L was suitable to the induction of callus from cotyledon and hypocotyl.The optimal hormone combination was MS+IAA 0.3 mg/L+6-BA 4 mg/L for the initiation of adventitious bud of cotyledon.The shoot regeneration percentage reached 67.5%.The optimal medium for the initiation of adventitious bud of hypocotyl was MS+KT 2 mg/L+NAA 0.2 mg/L.The shoot regeneration percentage reached 62.5%.Rooting was induced on 1/2 MS+NAA 0.1 mg/L,and the root inducting ratio reached 100% in 7 d. Conclusion A rapid plantlet regeneration system for C. morifolium is established from cotyledon and hypocotyl explants.Bud induction frequency is higher and the shoots in vitro grow vigorously.