Low Temperature Biodisinfection Effectiveness for Phytophthora capsici Control of Protected Sweet Pepper Crops in the Southeast of Spain

Abstract

Biodisinfection using fresh sheep manure in August is effective in controlling Phytophthora root rot in greenhouses in southeast Spain, but this is not the case after the beginning of September. The effectiveness of biodisinfection of new amendments has been evaluated beginning in October in sweet pepper greenhouses to control Phytophthora capsici. The amendments used were: T1: wheat husk + fresh sheep manure (FSM), 3.5 kg m−2; T2: sunflower pellets 3.5 kg m−2; T3: FSM: 3.5 kg m−2; T4: Control. Temperatures above 40°C were obtained in some amendments; anoxic conditions were found in all amendments, and also a reduction of the viability of P. capsici oospores with respect to the control, as well as a higher yield. The contribution of fresh sheep manure to the amendments did not lead to an improvement in their effectiveness. Autumn biodisinfection under low temperature conditions using fresh organic amendments that enhance soil anaerobic conditions may be a promising strategy for the control of P. capsici in pepper greenhouses in southeastern Spain.

Influence of Season and Organic Amendment on the Effectiveness of Different Biosolarization Treatments against Fusarium oxysporum f. sp. lactucae

“…The sunflower pellets were also effective in reducing oospores viability of the phytopathogenic fungus Phytophthora capsici in biodisinfestation trials under sub-optimal temperature conditions in Southeastern Spain, and it was related with its ability to increase anoxia conditions during exposure to the biodisinfestation treatment [45]. In trials in pots and soil amended with compost made from olive oil mill waste, aubergine plants showed less prominent symptoms and slower disease development on account of Verticillium dahliae through biological control mechanisms [45,46]. Different studies, such as those by Etxeberria et al [47] and Lacasa et al [8] showed that above the threshold of 35 • C the presence of the pathogens Phytophthora capsici and Phytophthora nicotianae began to decrease considerably.…”

Biocontrol of Diseases Caused by Phytophthora capsici and P. parasitica in Pepper Plants

“…Furthermore, the ability of Phytophthora to overcome the genetic resistance of plants owing to its genetic variability creates the need for alternative control methods for both diseases. Different cultivation techniques, such as grafting on resistant rootstocks [ 30 , 31 , 32 , 33 , 34 ] or nonchemical disinfection methods [ 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ], have been used as alternatives. Crop rotation is a key component in the integrated management of diseases caused by Phytophthora ; nevertheless, the survival of oospores, even in the absence of hosts, limits the effectiveness of these methods [ 21 , 44 ].…”

An optimized biofumigant improves pepper yield without exerting detrimental effects on soil microbial diversity

“…To address soil nutrient imbalances, crop productivity declines, and biodiversity losses [4], the South Korean government has devised long-term soil management action plans [5]. Some solutions suggested to address the challenges of continuous farming include crop rotation, soil solarization, and organic amendments [6,7].…”