|
Rot occurred onion base plate for the new town of Jiayuguan, Gansu Province conducted a survey to study the disease pathogens. Preliminary study on the onion varieties rot disease resistance of the base plate, indoor chemical screening for prevention and control the onion base plate rot, and chemical control tests carried out in the field. 1 the onion base plate rot symptoms: early onset of leaf yellowing, wilting or bent the the fertility peak onion bulbs side was soft rot like corruption, after expansion to stem disc, all serious aboveground wilting, stem disk brown dead. White or gray mold shaped humidity scales. Dry conditions, disease tissue the purple death or dead. The pathogenic findings the Fusarium oxysporum the largest share, 69.66%, 21.99% and 8.35%, while the proportion of Fusarium solani and Fusarium order. Indoor dish Pathogenicity Test results show that the the Fusarium oxysporum condition index was 60.2, the strongest pathogenic rot main pathogens causing onion base plate. Research the Jiayuguan new towns plate method 10 onion cultivars disease resistance identification. The results show that there are differences between the varieties of onion base plate rot resistance, Fusarium oxysporum shepherd boy from the resistant performance point of view, Kim Mi F1 moderately resistant (MR) varieties, the sun Green Lion is in a sense (MS) varieties, red classic, red 08, yellow 02, Zijin 505F1, Ruby 911F1 for a sense of the variety of disease (S), Europe Panther No. 1 variety is highly susceptible (HS). 3 indoor fungicides inhibit the growth of pathogens, but there are differences between the different pharmacy. Carbendazim, chlorothalonil, evil mildew blessing facilities bacteria grams of Fusarium oxysporum effective concentration (EC50) for 69.58,158.12,143.13,6.03 μg / mL, respectively, were Fusarium solani EC50 5 The 87,152. 76,35, 75 and 70. 12μg/mL, Fusarium EC50 49.53,2.11,4.48 and 126.61μg/mL. To facilities bacteria grams inhibition is the most prominent, carbendazim followed, chlorothalonil worst. Four agents correlation coefficient above 0.98, the drug concentration was positively correlated with inhibition. Field of chemical control test in seven pesticides as test materials, the onion field chemical test in the new town of Jiayuguan City, using a randomized block design, repeated four times. Harvest of each plot were measured by the incidence of the base plate of onion rot disease index, production and other indicators, the comprehensive evaluation. The results show that the control effect is good for 15% Avi. Poison EC 1500 times, 15% avermectin. Poison EC1000 times, reached 84.79%, 81.11%. Seen 15% yield monitor Avi. Poison EC 500 times, 15% of the the Avi. Poison EC 1500 times increasing effect of the two treatments, an increase of 14.23%, 8.54%, 40% phoxim EC 800 times handling cut 6.64%. 90% trichlorfon GR (0.6g), 40%, phoxim EC 400 times, 90% trichlorfon GR (1.2g) the three processing yield differences.
|