Aflatoxin contamination in groundnut by Aspergillus section Flavi is a major pre- and post-harvest problem causing kernel-quality loss. Post-harvest aflatoxin contamination is caused initially by infestation of aflatoxigenic strains at the pre-harvest stage, resulting in reduced kernel quality after harvest. Improper handling of pods and storage methods after harvest lead to high moisture and ambient temperatures, directly causing aflatoxin contamination. In this review, we report the extent of post-harvest contamination along the groundnut value chain in the Kolokani, Kayes, and Kita districts of Mali in West Africa. Groundnut kernels and paste samples were collected from retailers in selected markets from December 2010 to June 2011, and aflatoxin B1 (AFB1) content was estimated. Aflatoxin was significantly higher in groundnut paste than in kernels. Kolokani recorded the highest toxin levels in both kernels and groundnut paste compared with the other districts. Overall, AFB1 levels in kernels and paste increased during storage at the market level in the three districts and were above permissible levels (≯20 μg/kg). The effect of weather factors on post-harvest contamination and the reasons for aflatoxin build-up in Mali are discussed. This paper also highlights different management tools for reducing post-harvest aflatoxin contamination, such as post-harvest grain handling, post-harvest machinery, physical separation, storage methods and conditions, disinfestation, detoxification, inactivation, filtration, binding agents, and antifungal compounds. Post-harvest management options and enhanced use of good agricultural practices for mitigating this problem in Mali are also presented.

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1 groundnut (Arachis hypogaea L.) in Mali, West Africa 2 3 ABSTRACT 13 Groundnut is a major source of livelihood for the rural poor in Mali. However, the crop is 14 prone to pre-and post-harvest aflatoxin contamination caused by Aspergillus flavus and A. 15 parasiticus. Therefore, to minimize health related hazards from exposure to aflatoxin 16 contaminated food, information on the prevalence and distribution of aflatoxins (AFB1) in 17 the groundnut value chain in Mali is needed for timely interventions. To this end, a study was 18 undertaken in three districts (Kayes, Kita and Kolokani) to assess aflatoxin contamination in 19 the field and storage. Ninety pod samples in each district were collected from fields (30 20 villages/district and 3 samples/village) during 2009 and 2010. Pre-harvest contamination was 21 estimated at harvest, whereas samples for post-harvest contamination were collected from 22 granaries of the same farmers at a monthly interval for 3 months. The villages in each district 23 were categorized into safe, acceptable, moderate risk and high risk areas based on pre-harvest 24 AFB1 levels. Kayes recorded more pod samples (77%) within 20 µg/kg of pre-harvest 25 aflatoxins followed by Kolokani (55.6%) and Kita (45.6%) based on 2009 and 2010 mean 26 values. Toxin concentrations at harvest were comparatively less in Kayes during both years. 27 Further, Kayes had more villages under safe and acceptable limits when compared to 28 Kolokani and Kita. Overall, 46 out of 90 villages in the three districts had acceptable pre-29 harvest toxin limits. Further, 12 villages in Kolokani were in the high risk category. An 30 increase in toxin levels was noticed with period of storage during both years. Comparatively, 31 toxin levels after storage were least in Kayes during 2009. Kayes also recorded less AFB1 32 levels in 2010 after Kita. Our results indicate that Kayes is relatively safe over Kita and 33 Kolokani in pre-harvest aflatoxin contamination. The reasons for district-wide variations in 34 pre-harvest contamination; and the reasons for post-harvest flare up of the problem are 35 discussed. Further, proper storage of pods at farmers' granaries in Mali is suggested to 36 overcome the problem from reaching alarming levels. 37 38

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Late leaf spot (LLS) (Phaeoisariopsis personata) and rust (Puccinia arachidis) are major foliar diseases of peanut causing significant losses worldwide. Identification and infusion of resistance into peanut cultivars is important in the management of these diseases. The present study therefore aimed at screening the peanut mini core collection to identify potential sources of resistance to these diseases. Two separate field experiments were conducted for screening LLS and rust under artificial epiphytotic conditions during rainy seasons of 2012 and 2013 at ICRISAT, Patancheru, India. The trials were laid in a randomized complete block design on beds with three replications. Data on LLS and rust disease severities were collected using 1 to 9 scales at 75, 90 and 105 days after sowing (DAS), and pod yields were recorded at harvest. Results indicate significant variations among accessions for LLS and rust resistance. Mean of 2 years study revealed that 53 accessions were moderately resistant (MR), 86 accessions were susceptible (S) and 45 accessions were highly susceptible (HS) to LLS. For rust disease, 10 accessions were resistant (R), 115 accessions were with 'MR' reaction and 59 accessions with susceptible (S) reaction. Six superior accessions in terms of combined disease resistance and yield (ICGs 4389, 6993, 11426, 4746, 6022, 11088) were selected and the disease progress curves, for each, were generated. Highest yields were recorded with ICG 11426 in LLS and rust plots. Overall, our results indicate that these six accessions can be potential sources of LLS and rust resistance.

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Aflatoxin contamination in groundnut byAspergillus flavus has assumed global significance and is considered a potential threat to human and animal health. The present study focused on the screening and identification of stable and reliable resistance sources to pre-harvest aflatoxin contamination in ICRISAT's groundnut mini core germplasm accessions. . In total, 31 accessions had less aflatoxin accumulation than the resistant check, 55-437. The seven best accessions, ICGs 13,603, 1415ICGs 13,603, , 14,630, 3584, 5195, 6703 and 6888, over six years (2008ICGs 13,603, -2013 consistently accumulated very low levels of aflatoxin (<4 μg kg −1). These seven accessions could be potential sources for understanding the resistant mechanisms and can be further used in developing resistant cultivars or introgressing resistance in popular released varieties.

Rice sheath blight disease (ShB), caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral ® , the commercial liquid formulation of Bacillus subtilis strain MBI 600, against rice ShB and for plant growth promotion. In greenhouse studies, four log concentrations of Integral (from 2.2×10 6 to 2.2×10 9 cfu/mL) were used as seed treatment (ST). After 25 d, seedlings were dipped (SD) into Integral prior to transplanting. At 30 d after transplanting (DAT), leaf sheaths were inoculated with immature sclerotia of the pathogen. At 45 DAT, a foliar spray (FS) with Integral was applied to some treatments. The fungicide control was 50% carbendazim at 1.0 g/L, and a nontreated control was also included. Overall, there were 10 treatments, each with five replications. ShB severity was rated at 52 DAT, and seedling height and number of tillers per plant were rated at 60 DAT. In 2009, two field trials evaluated Integral at 2.2×10 8 and 2.2×10 9 cfu/mL. Integral was applied as ST, and seedlings were produced in a nursery bed. After 32 d, seedlings were treated with Integral as SD and transplanted into 10 m 2 blocks. Foliar sprays were given at 45 and 60 DAT. There were seven treatments, each with eight replications arranged as a factorial randomized complete block design. At 20 DAT, the plots were broadcast inoculated with R. solani produced on rice grains. Seedling height before transplanting, ShB severity at 90 DAT, and grain yield at harvest were recorded. Integral at 2.2×10 9 cfu/mL provided significant increase of seedling heights over other treatments under greenhouse conditions. The Integral treatments of ST + SD + FS at 2.2×10 9 cfu/mL significantly suppressed ShB over other treatments. In field studies, Integral provided significant increase of seedling height in nursery, and number of tillers per plant, compared with the control. ShB severity was significantly suppressed with higher concentrations of Integral compared to lower concentrations. Grain yield were the highest at an Integral concentration of 2.2×10 9 cfu/mL. Overall, Integral significantly reduced ShB severity, enhanced seedling growth, number of tillers per plant and grain yield as ST + SD + FS at the concentration of 2.2×10 9 cfu/mL under the conditions evaluated.