Impact of the Aerobic Mesophilic Microorganisms on Black Sigatoka of Bananas According to the Cropping Systems in the Region of Kisangani (Case of the old secondary forest)

The microorganisms play crucial roles in the cycle of matter and damage the organic substances, sources of electrons, source of carbon, source of energy for their biosynthesis. While dying, the microorganisms contribute on their turn to enrich soil in different composed of the carbon. In this work, we studied the impact of the aerobic mesophiles microorganisms on the black sigatoka of banana in the old secondary forest. The objective was to count and to identify the microbial diversity of the forest ecosystems, as well as to study their impact on the development of the black sigatoka of banana around the forest reserve of Masako. The assessment of the microbial populations has been done in an experimental field according to a device in blocks of Fischer by the method of successive dilutions of coloration of Gram and by the discharge of ascospores. The results showed that the rain season was lower in total microbial biomass (700, 7 colonies) than the subdry season (840,3 colonies). The Bacillus genera have been more represented more than the Coccus genera. The impact of black sigatoka of banana was raised at the cultivar Libanga Likale (40%) and low at Yangambi 5 Km (14%). The distribution of microorganisms in depth in the sub-dry season to the level of surface with vegetation was considerable either 3819, 3. 103 UFC( UNIT FORMAT COLONY) by gram of soil between 0 and 5 cm against 2754,5.103 UFC by gram of soil between 15 and 20 cm. This suggests that the raised number of microorganisms could have positive impact on soil fertility by decreasing the illnesses in this ecosystem.

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Illuminance affects epidemiological parameters of banana Yellow Sigatoka in Brazil

10.1101/828848 ◽

2019 ◽

Author(s):

Djalma M. Santana-Filho ◽

Milene C. da Silva ◽

Jorge T. de Souza ◽

Zilton J. M. Cordeiro ◽

Hermínio S. Rocha ◽

...

Keyword(s):

Logistic Regression ◽

Survival Analysis ◽

Cropping Systems ◽

Leaf Age ◽

Cropping System ◽

Black Sigatoka ◽

Light Interference ◽

Leaf Spots ◽

Leaf Necrosis ◽

Epidemiological Parameters

ABSTRACTThe Sigatoka leaf spots are among the most important banana diseases. Although less damaging than black sigatoka, yellow sigatoka (Pseudocercospora musae) still prevails in some regions. This study aimed at testing the hypothesis of light interference in monocyclic parameters of yellow sigatoka epidemics. Grande Naine plantlets kept under contrasting shading conditions had their leaves 1 and 2 inoculated. Evaluations were performed for 60 days. For each inoculated leaf, the time until symptom onset (incubation), presence of infectious lesions (latency), and disease severity (extensive leaf necrosis) according to Stover’s scale modify per Gauhl (1994), called here only Stover’s scale, were registered. Logistic regression was used to assess the relative occurrence risk and survival analysis was used to check the effects of variables on relevant epidemiological parameters. The risks of sporulation and of reaching high severities were lower for plants kept under shading regardless of the acclimation conditions and no effect of leaf age was detected. The logistic regression showed symptoms appearing in both conditions (p=0,85), but have significance difference in occurrence of latent lesions (p=0,013) and necrosis (p<0,0001). The necrosis risk in non-shaded environment arrived 66%. The survival analysis showed significance difference in the time to appear the symptom evaluated in all tested variables (p<0,0001) in function of the cropping system. Lower illuminance negatively affected the incubation, latency and infectious periods, and severity. A shaded system could be tested to produce organic bananas in areas of high risk of occurrence of Yellow sigatoka disease.Significance and Impact of the StudyYellow Sigatoka (Pseudocercospora musae) is a banana disease that can cause severe damage if left uncontrolled. Its control is based mostly on fungicides.Our results show that shading downregulates the epidemiological parameters of that disease such as incubation, latent and infectious periods, and symptom’s severity. These results can be the basis for testing alternative cropping systems and producing organic bananas.

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Epigeal fauna and soil attributes in a cover-cropped organic vegetable system

Ciência Rural ◽

10.1590/0103-8478cr20200842 ◽

2021 ◽

Vol 51 (8) ◽

Author(s):

Sandra Santana de Lima ◽

Dérique Biassi ◽

Cyndi dos Santos Ferreira ◽

Priscila Silva Matos ◽

Lucas Vasconcelos Rocha ◽

...

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Secondary Forest ◽

Cropping Systems ◽

Block Design ◽

Solanum Melongena ◽

Chemical Properties ◽

Cropping System ◽

Positive Association ◽

Forest Site

ABSTRACT: This study assessed the effect of cover crop biomass on the epigeal fauna of an organic eggplant (Solanum melongena L.) cropping system. A randomized block design was used, with four cover crop treatments: brachiaria, crotalaria, millet, and cocktail (brachiaria, crotalaria and millet). The epigeal faunal indices were determined at each plot. The epigeal fauna of a secondary forest site was also assessed for comparison. Epigeal individuals were collected using pitfall traps at two sampling periods (110 and 180 days after mowing cover crops). Soil samples were collected for determination of physical and chemic properties. 2032 individuals were captured in the first sampling and 3806 individuals in the second. The highest values of wealth in the first collection were observed in the millet and cocktail areas. Cluster analysis showed similarity of epigeal faunal groups between millet and brachiaria plots at the first sampling and between cocktail and crotalaria sites at the second sampling. Co-inertia analysis showed a significant covariance between epigeal fauna at the second sampling and soil properties. The cover crops management had a beneficial influence on the activity, wealth and ecological indexes, in both sampling periods. The positive association observed between epigeal faunal groups and soil physical and chemical properties demonstrates the efficiency of cover crops in improving soil quality in organic cropping systems.

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Devising fertiliser recommendations for diverse cropping systems in a region: the case of low-input bean/maize intercropping in a tropical highland of Haïti

Agronomie ◽

10.1051/agro:2003046 ◽

2003 ◽

Vol 23 (7) ◽

pp. 673-681 ◽

Cited By ~ 9

Author(s):

C. Clermont-Dauphin ◽

J. M. Meynard ◽

Y. M. Cabidoche

Keyword(s):

Cropping Systems ◽

Low Input

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The arbuscular mycorrhiza fungusRhizophagus irregularisMUCL 41833 decreases disease severity of Black Sigatoka on banana c.v. Grande naine, underin vitroculture conditions

Fruits ◽

10.1051/fruits/2014041 ◽

2015 ◽

Vol 70 (1) ◽

pp. 37-46 ◽

Cited By ~ 10

Author(s):

Corinne Coretta Oye Anda ◽

Hervé Dupré de Boulois ◽

Stéphane Declerck

Keyword(s):

Arbuscular Mycorrhiza ◽

Disease Severity ◽

Black Sigatoka

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Spider diversity in the Bukit Timah Nature Reserve, Singapore

Gardens’ Bulletin Singapore ◽

10.26492/gbs71(suppl.1).2019-08 ◽

2019 ◽

Vol 71 ((suppl.1)) ◽

pp. 209-243

Author(s):

J.K.H. Koh ◽

D.J. Court

Keyword(s):

Nature Reserve ◽

New Records ◽

Secondary Forest ◽

Distinct Species ◽

Primary Forest ◽

Preliminary Results ◽

Vegetation Zones ◽

Comprehensive Survey ◽

Quantitative Analyses ◽

First Time

This paper discusses the preliminary results of the first comprehensive survey of the spiders of the Bukit Timah Nature Reserve (BTNR) in Singapore. Two plots were established in each of the three zones of vegetation, viz., primary forest, old secondary forest, and maturing secondary forest. They were repeatedly sampled over an 18-month period. Sorting of the collection so far suggests that the three vegetation zones harbour rather different spider assemblages. Only ~9% of the total spider fauna recovered was shared by all three zones. The results have also yielded a preliminary picture of dominance, abundance and rarity. Although first intended to obtain a baseline for future quantitative analyses, the survey became a testing ground to modify and refine methodology so as to conduct future quantitative surveys with greater scientific rigour. Taxonomic work on the samples so far shows that the spiders in the BTNR span over 43 families, of which six families are listed for the first time in Singapore. The tally is summarised in an interim checklist of BTNR spiders. The checklist, with a total of 317 entries, shows that there are 158 described species of spiders in BTNR, of which 25 species are new records for Singapore. Another 159 morphospecies are provisionally recognised as distinct species, some of which may be new to science. Our observations during the survey have allowed us to provide a narrative of BTNR spider diversity against a backdrop of their microhabitat specialisation.

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Utilisation of wild growing yams as supplementary nutrition and its impact on the dry forest ecosystem in north-western Madagascar

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2004.0080 ◽

2004 ◽

Vol 155 (3-4) ◽

pp. 80-88 ◽

Cited By ~ 6

Author(s):

Klaus Ackermann

Keyword(s):

Forest Ecosystem ◽

Rainy Season ◽

Secondary Forest ◽

Local Population ◽

Dry Forest ◽

Dry Forests ◽

Supplementary Food ◽

Wild Yams ◽

Supplementary Nutrition ◽

North Western

Wild growing yams (Dioscorea spp.) are an important supplementary food in Madagascar, especially during periods of rice shortage in the rainy season. Yams grow in dry forests and there is a particularly high occurrence of yam tubers in recently burned, open secondary forest formations. The study found that the uncontrolled harvest of yams can contribute to the degradation of dry forests due to the high quantity of wild yams harvested by the local population and the widespread practice of intentionally burning forests to increase yams production.

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Growth and Economic Profitability of Castor Cultivation in the Semi-arid Zone of Haryana

Indian Journal of Economics and Development ◽

10.35716/ijed/ns20-011 ◽

2020 ◽

pp. 300-305

Keyword(s):

Arid Zone ◽

Cropping Systems ◽

Descriptive Analysis ◽

Market Price ◽

Transportation Cost ◽

Castor Seed ◽

Production Constraints ◽

Net Profit ◽

Semi Arid ◽

Extract Information

The present study was carried out in three districts viz; Rewari, Sirsa and Hisar of Haryana state. A survey of 60 sampled farms was conducted to extract information pertaining to various expenses incurred in cultivation of castor and output attained as well as to ascertain the perception of farmers for various problems encountered in production and marketing of castor seed. The descriptive analysis was employed to draw valid inferences from the study. The results revealed that net profit accrued from cultivation of castor seed was ₹ 46331 ha -1 in the study area. The value of B: C ratio of castor cultivation was more than one and also higher as compared to prevalent cropping systems indicated that cultivation of castor seed is economical viable entity. However, production constraints like retention of F2 seed in the field over year, grain scattering, shortage of irrigation water, frost effect on crop yield and marketing constraints like absence of MSP, higher transportation cost sale of castor seed in distant markets, frequent fluctuation in market price, non-availability of processing units were observed.

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Comparative Effect of Groundnut (Arachis hypogea l.) Genotypes on Yield and N Fixation in Sudan and Northern Guinea Savannahs of Nigeria

10.36265/njss.2019.290208 ◽

2019 ◽

pp. 61-67

Keyword(s):

Agricultural Research ◽

Cropping Systems ◽

Block Design ◽

Dry Weight ◽

Field Trials ◽

Yield Potential ◽

N Fixation ◽

Maize Crop ◽

Significant Interaction Effect ◽

Pod Yield

Recognition of high yielding and nitrogen (N) fixing groundnut genotypes and desegregating them in the cereal-based cropping systems common in savannah regions will enhance food security and reduce the need for high N fertilizers hence, minimize the high cost and associated environmental consequences. Field trials were conducted during the 2015 growing season at the Research Farms of Bayero University Kano (BUK) and Institute for Agricultural Research (IAR), Ahmadu Bello University, Samaru-Zaria to assess the yield potential and Biolog- ical N fixation in 15 groundnut genotypes (ICG 4729, ICGV-IS 07823, ICGV-IS 07893, ICGV-IS 07908, ICGV- SM 07539, ICGV- SM 07599, ICGV-IS 09926, ICGV-IS 09932, ICGV-IS 09992, ICGV-IS 09994, SAMNUT-21, SAMNUT-22, SAMNUT-25, KAMPALA and KWANKWAS). The groundnut genotypes and reference Maize crop (SAMMAZ 29) were planted in a randomized complete block design in three replications. N difference method was used to estimate the amount of N fixed. The parameters determined were the number of nodules, nod- ule dry weight, shoot and root dry weights, pod, and haulm yield as well as N fixation. The nodule dry weight, BNF, haulm, and pod yield were statistically significant (P<0.01) concerning genotype and location. Similarly, their interac- tion effect was also highly significant. ICGV-IS 09926 recorded the highest nod- ule dry weight of 2.07mg /plant across the locations while ICGV-IS 09932 had the highest BNF value of 140.27Kg/ha. Additionally, KAMPALA had the high- est haulm yield, while ICGV-IS 07893 had the highest pod yield across the loca- tions with a significant interaction effect. The result shows that ICGV-IS 07893 and ICGV-IS 09932, as well as ICGV-IS 09994 and SAMNUT – 22, were the best genotypes concerning BNF, haulm and pod yield in the Northern Guinea and Sudan Savannahs of Nigeria respectively with the potential for a corresponding beneficial effect.

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