Modification and Properties of Cellulose Nonwoven Fabric—Multifunctional Mulching Material for Agricultural Applications

The paper describes a method of modifying a commercial viscose nonwoven fabric and its use as a modern mulching material in agriculture. The conducted research confirmed that the proposed modification of the viscose nonwoven fabric could be successfully used as a multipurpose and, above all, completely biodegradable nonwoven crop cover, which will eliminate the problem of disposal after the harvest period. Modified cellulose nonwoven fabric was obtained by staining with NB—BT helion brown, then padding with potassium nitrate (KNO3) solution (used as a fertilizer) and finally coating with polylactide (PLA) solution. The characterisation of the nonwoven fabric included structural analysis, physicochemical properties and mechanical tests. The modified cellulose nonwovens were used in the tunnel cultivation of tomatoes as a heat-retardant, water-absorbing, antiweed mulching material that prevents soil infestation and slowly releases fertilizers.

Cropping Systems of Fenugreek with Faba Bean to Reduce Broomrape Infestation

Background: Broomrape (Orobanche crenata Forsk.) is a major threat to faba bean and an important danger parasite. An intercropping is a necessity to curb the spread and progress of the parasite before it leads to much more economic losses. The current study was aimed to evaluate intercropping of fenugreek with faba bean under two plant densities of both crops on broomrape incidence to increase faba bean yield, land usage and economic return in heavy soil infestation of broomrape.Methods: This study was carried out at Giza Agricultural Research Station (Lat. 30°002 303 N, Long. 31°122 433 E, 26 m a.s.l), Agricultural Research Center, Giza, Egypt. During the winter season of 2017/2018 and 2018/2019 seasons, sixteen treatments were the combinations between two ridge widths (60 “narrow” and 120 cm “wide”) and six cropping systems (50% faba bean + 50% fenugreek, 100% faba bean + 50% fenugreek, 50% faba bean + 100% fenugreek, 100% faba bean + 100% fenugreek, 50% sole faba bean and 100% sole faba bean), as well as sole plantings of fenugreek under heavy soil infestation of broomrape. A split-plot design with three replicates was used. Ridge widths were assigned in the main plots and cropping systems were arranged in sub plots. Result: Growing faba bean plants in wide ridges had physical barriers with stamping of the vascular system against the parasite. 50% faba bean + 100% fenugreek had higher soil total phenols in faba bean rhizosphere than the others. Growing 50% faba bean + 100% fenugreek in wide ridges had lower number of spikes per m2 and spikes dry weight per m2, meanwhile, growing 100% faba bean + 100% fenugreek in wide ridges had higher seed yields of both crops per ha, land usage and economic return. Growing two rows of faba bean (100% of sole cropping) in both sides of wide ridge (120 cm width) with four rows of fenugreek (100% of sole cropping) in middle of the ridge could be an integrated control strategy to increase faba bean productivity, land usage and economic return under heavily soil infested of broomrape.

Giant sumpweed (Cyclachaena xanthiifolia (Nutt.) Fresen.): seed stocks, seedling dynamics, methods control

Goal. To assess the degree of danger of contamination of the sowing layer and an increase in stocks of Giant sumpweed seeds in the soil, the timing and dynamics of seedlings emergence, to develop a control pathway aimed at their reduction. Methods. The studies were carried out by route-expeditionary surveys and field experiments. The potential soil contamination was determined washing weed seeds from soil samples. Weeds were counted in 4—6-single repetitions. Results. In ruderal biotopes, the infestation of 0—20 cm of the soil layer by weed seeds has not changed since 2009 and amounted to 244.6—384.1 thousand pcs./m2. At the same time, the infestation of soils with Giant sumpweed seeds increased 2.0—2.7 times. In crops of cultivated plants, the total weediness of the soil increased by 1.8—3.5 times, and Giant sumpweed — by 4.7—12.1 times and reached 25.0—85.0 and 14.5—15.5 thousand pcs./m2, respectively. Seed germination of Giant sumpweed was observed only in the spring and early summer periods. In the Dry and Southern Steppe, Giant sumpweed emerged in the middle-end of March, in the Northern Steppe — during April, Forest-Steppe — from early May to early June. In crops of cultivated plants the density of young crops of Giant sumpweed did not exceeded 23—62 pcs./ m2, and on uncultivated lands — from 636 to 862 pcs./m2. On uncultivated lands the effective control in crops of Giant sumpweed was carried out by mowing weeds, in crops of cereals — by herbicides of leaf action in the tillering stage, late arable crops by pre- and after emergence harrowing combined with inter-row cultivation. Conclusions. Potential soil infestation by seeds of Giant sumpweed in ruderal biotopes since 2009 increased by 2.0—2.7 times, and in crops of cultivated plants — by 4.7—12.1 times and reached 25.0—85.0 and 14.5—15.5 pcs./ m2 thousand, respectively. Seed germination of Giant sumpweed occurred only in spring and early summer. The number of seedlings on ruderal areas reached 636—862 plants/m2, and in crops — 23—62 plants/m2. Effective control of Giant sumpweed on uncultivated lands was achieved by mowing weeds, in sowing of grain crops with leaf herbicides in the tillering phase, row crops — by pre-emergence and post-emergence harrowing in combination with inter-row cultivation.

Infections of bean plant and field soil are linked to region, root rot pathogen, and agro-ecosystem

SummaryUnderstanding pathogen-agrosystem interaction is particularly essential when applying a control method to minimize pathogen prevalence prior to plant infection. To meet this requirement, frequency of major root rot pathogens isolated from bean root and seed, and their soil populations were examined in farmers’ fields. Multivariate analyses evidenced more frequent isolations of Fusarium solani and Rhizoctonia solani from root and seed compared to Macrophomina phaseolina and Fusarium oxysporum. Two Fusarium species had denser soil populations than R. solani and M. phaseolina. More frequent isolations of pathogens were detected in root and seed collected from Abhar and Khodabandeh compared to Kheirabad region. Agronomic and soil variables corresponded less closely to root infections compared to soil infestation and seed infections. Bean market class, herbicide application, and planting depth were linked to root, seed and soil infestations. Such information provides a basis for increased confidence in choosing appropriate control strategies for a pathogen and region in sustainable agriculture.

Physiological changes in Solanum lycopersicum L. in the presence of root-knot nematodes and salicylic acid

Nematodes of the genus Meloidogyne spp. are one of the tomato culture’s main pathogens. According to their soil infestation level, physiological changes may occur. Consequently, it is extremely important to employ given products to minimize their effect. A feasible option is the salicylic acid, a phytohormone that can induce into resistance due to its ability to increase the production level of some pathogenicity proteins. Therefore, the purpose hereof was to assess the effect of salicylic acid on the physiology of tomato plants subject to different populational densities of Meloidogyne javanica. The design employed was one of randomized blocks, in an incomplete factorial scheme, using the Box Central Compound (BCC) matrix with five nematode populational densities (PD) (0; 5815; 20000; 34184; and 40000 eggs per plant) and five salicylic acid doses (0.0; 0.29; 1.0; 1.71; and 2.0 mM), with four repetitions and two plants per experimental patch. The gas exchanges, fluorescence, and chlorophyll levels were evaluated 45 days after the transplant and soil infestation. The data were submitted for analysis of variance through the F test and, in the significance cases, the polynomial regression analysis was performed. For stomatal conductance, a greater reduction was seen at the PD of 21755 eggs per plant, a fact that might have decreased the liquid assimilation of CO2 and the efficiency of carboxylation. The salicylic acid (SA) affected the CO2 liquid assimilation and the efficiency of carboxylation. The infestation of M. javanica in tomato plants negatively affected the gas exchange and the chlorophyll levels because the SA application did not mitigate the negative effect thereof.

First Report of Root Rot Caused by Phytophthora bilorbang on Olea europaea in Italy

Leaf chlorosis, severe defoliation and wilt associated with root rot were observed on mature olive trees cv. Nera di Gonnos in an experimental orchard at Mirto Crosia (Calabria, southern Italy). An oomycete was consistently isolated from rotten roots of symptomatic olive trees. It was identified as Phytophthora bilorbang by morphological characters and sequencing of Internal Transcribed Spacer (ITS) regions of ribosomal DNA (rDNA). Pathogenicity was verified by inoculating potted two-month-old rooted cuttings of Olea europaea var. Nera di Gonnos in a soil infestation trial. P. bilorbang was re-isolated from roots of symptomatic, artificially inoculated olive cuttings to fulfill Koch’s postulates. This is the first report of P. bilorbang on O. europaea L. and on a species of the Oleaceae family worldwide.

Detection and Characterization of Fusarium oxysporum f. sp. vasinfectum VCG0114 (Race 4) Isolates of Diverse Geographic Origins

A highly virulent cotton wilt pathogen, Fusarium oxysporum f. sp. vasinfectum VCG0114 (race 4) was found in West Texas in 2017, after being known in California since 2001. Isolates obtained from wilted plants collected in 2017 from Texas, in 2015 from China, and during 2001 to 2014 from California and isolates from historical collections including the race 4 reference isolate were characterized by soil-infestation pathogenicity assays, DNA sequence analysis, and vegetative compatibility analysis. All obtained F. oxysporum f. sp. vasinfectum isolates belonged to VCG0114. All of these isolates, except one isolate from China, caused disease in a soil-infestation assay without nematodes. Thus, they belong to the nematode-independent pathotype. Texas isolates were significantly more virulent than were isolates from China or California on Gossypium barbadense ‘Pima S-7’. Four different genotypes (N, T, MT, and MiT) were identified based on the transposable element Tfo1 insertion into the PHO gene and independent MULE or MITE insertions into the Tfo1 transposon. Some significant differences in virulence were detected among the genotypes in some locations. No differences in pathogenicity were observed between the California and China collection isolates on Pima S-7, and the virulence of the major genotypes was similar on the Gossypium hirsutum cultivar ‘Stoneville 474’ or the Barbren 713 germplasm line. Simple polymerase chain reaction (PCR) methods were developed to specifically determine and detect the four genotypes within VCG0114. A specific PCR method to detect all VCG0114 isolates was also developed. These methods will facilitate the timely identification of infested fields and seed lots and the elucidation of evolutionary relationships among the isolates. This should help to closely monitor the movement of the pathogen and reduce dissemination of these devastating pathogens.

African Nightshade and African Spinach Decrease Root-Knot Nematode and Potato Cyst Nematode Soil Infestation in Kenya

Plant-parasitic nematodes, particularly root-knot nematodes (RKN: Meloidogyne spp.) and cyst nematodes (CN: Globodera and Heterodera spp.) cause severe yield reduction in most cultivated crops and are of high economic importance. African nightshade (Solanum spp.) and African spinach (Amaranthus spp.) are important African indigenous vegetables (AIV) and are rich sources of nutrition and income. However, their host status to plant-parasitic nematodes remains largely speculative. Therefore, a survey was conducted which revealed that S. villosum exhibited high root galling, whereas on S. scabrum, A. cruentus, and A. dubius root galling was rare or very low. Additionally, soil collected from the rhizosphere of S. villosum and S. scabrum contained few cysts of potato cyst nematodes (PCN), and no developing PCN females were observed on the roots of growing plants. Therefore, we studied the dynamics of RKN and PCN on A. dubius, A. cruentus, S. scabrum, and S. villosum over 2 years in a field experiment. The effects of AIV crop species on RKN and PCN soil infestation were evaluated using susceptible S. lycopersicum or S. tuberosum. After first, second, and third cultivation of A. dubius, A. cruentus, and S. scabrum, RKN infestation of the soil decreased by more than 85%, whereas S. scabrum and S. villosum decreased PCN densities by more than 80%. When cropping susceptible crops, after three seasons of successive cultivation of these AIV, galling index and number of developing PCN females measured on susceptible crops decreased by more than 75%. Wilting and RKN-PCN coinfection incidences also decreased significantly. Here, we present data that support the development of a novel cropping system including African spinach and African nightshade, which reveals a high potential to manage RKN and PCN in an environmentally friendly, effective, and productive way.

Research article Comparison of artificial screening methods for evaluation of resistance to Fusarium wilt disease of castor (Ricinus communis L.)

This study was carried out to compare two artificial screening methods viz. Soil Infestation method (SIM) and root dip inoculation technique (RDIT), under glasshouse conditions for the screening of resistant to Fusarium wilt. Both the artificial screening methods; SIM and RDIT were statistically similar in respect of wilt incidence. However, the reaction exhibited by the castor genotypes was varied with artificial screening methods. Mean wilt incidence obtained through SIM (53.9%) was higher as compared to RDIT (44.8%). All the genotypes exhibited comparatively higher wilt incidence when screened through SIM as compared to RDIT. Genotype DCS 9 exhibited resistant reaction (15.8 %) when screened through RDIT but was moderately resistant (32.5 %) when screened through SIM. It was concluded that SIM could also be used for screening of castor genotypes for the resistance to Fusarium wilt disease. However, lower level of resistance could be evaluated efficiently with saving 8-10 days through RDIT as compared to soil infestation method.