Abstract: In order to explore the best sowing date for high yield of peanuts in saline-alkali land, a staged sowing comparative test of direct-seeded peanuts covered with plastic film was carried out in the representative area of ​​saline-alkali land in the Yellow River Delta. Using methods such as variance analysis and chi-square test, the difference analysis of peanut development process, growth volume and yield factors of the six set sowing dates were carried out, and the best sowing date was selected by calculating the climate accumulated frequency. The results showed that the peanut development period shortened with the delay of sowing date. If the sowing date is too early, the low temperature in the seedling stage will lead to a low emergence rate and affect the yield. If the sowing date is too late, the seedling stage is prone to high temperature weather causing vigorous seedlings or burning seedlings, and the short flowering-needle period will reduce the number of seedlings and pods, which will affect the yield formation. Sowing at the right time avoids the disadvantages of early or late sowing. In addition, the pod has a long maturity period, which is beneficial to dry matter accumulation and yield improvement. Peanuts sown too late are prone to prosperous growth in the early stage and premature aging in the later, while peanuts sown in the suitable period have a balanced and coordinated growth distribution, which is more conducive to the transfer of dry matter from “source” to “store” to increase the weight of the pod. The yield of peanuts sown too early or too late was reduced by more than 10% compared with the control, and the yield and 100-seed weight of the peanuts sown in the suitable period were significantly better than other sowing dates. The suitable sowing date for the test year is during the first day when the average daily temperature is stable and passing 13−20℃. The suitable sowing date throughout the year is generally from April 26th to May 9th, and the best sowing date is from May 2nd to 5th. During the period, the planting temperature conditions were stable and sufficient, which can effectively bring out the high yield potential of saline-alkali peanut.

Key words: Yellow River Delta, Saline-alkali land, Peanut, High yield, Suitable sowing time