As the protected vegetables enter their peak production period, they also experience a high demand for water and nutrients. It is essential to fully understand the fertilizer needs of these crops during this critical phase in order to apply fertilizers in a scientific and rational manner.
During the fruiting stage, the nutrient uptake ratios of nitrogen, phosphorus, and potassium differ from those in the early growth stages. At this time, the plant requires more potassium, a stable amount of phosphorus, and an increased but relatively lower amount of nitrogen compared to potassium. However, many farmers believe that phosphate fertilizer, urea, and ammonium bicarbonate are suitable for fruit development, and they often think that applying more fertilizer will lead to higher yields. This misconception has led to excessive nitrogen and phosphorus application, while potassium levels remain insufficient.
Excessive nitrogen can cause larger leaf areas and darker green foliage. In severe cases, the leaves may become thick, hard, and twisted, and the fruits may be reduced or misshapen. Over-application of phosphate fertilizer can lead to symptoms like chlorosis due to deficiencies in zinc, iron, and magnesium, as the phosphate binds with these elements in the soil, reducing their availability.
A lack of potassium results in scorched edges on older leaves, increased fruit cracking, reduced sugar content, poor flavor, and premature plant decline. To avoid these issues, it's recommended to apply fertilizers in small amounts and focus on potassium supplementation. If trace elements need to be added, foliar sprays are an effective method.
In addition, as temperatures inside the greenhouse rise, symptoms such as tomato umbilical rot or the browning of cucumber tips may appear. These are typically caused by calcium deficiency. Rapid temperature increases can hinder water absorption and disrupt calcium transport within the plant, leading to calcium deficiency at the growing tip. The solution is to regulate greenhouse temperatures, avoid drastic fluctuations, ensure timely watering, and apply calcium foliar sprays.
As outdoor temperatures increase, the population of viral vectors like aphids and whiteflies also rises. Pest control becomes crucial to prevent the spread of viral diseases. Installing insect nets is an effective and cost-efficient measure. All vents in the greenhouse should be covered with clear insect nets. A disinfectant tank should be placed at the entrance, and lime should be used inside for foot disinfection. A 10% trisodium phosphate or 0.1% potassium permanganate solution should be prepared in the temperature chamber for hand disinfection. For aphid control, spraying with 25% AKTA diluted 7,500 to 10,000 times is recommended. These measures can significantly reduce the risk of viral disease transmission.
Author: Tense
Source: Rural Newspaper
ã€Comment】 ã€Print this article】 ã€Close this page】 ã€Large, medium and small】
Aluminium Alloy,Heavy Door Hinge,Aluminium Alloy Door Hinges,Frameless Cabinet Hinges,Home Depot Cabinet Hinges,Adjusting Door Hinges,stable and durable,design with 7 mounting holes