A study on the characterization of monsoon rainfall for sorghum (Sorghum Vulgare Pers) and its response to typical rainfall patterns

Twenty eight years (1962-89) rainfall of Nagpur was analysed and the rainfall suitability at various probability levels for sorghum crop was studied. The total rainfall during kharif season (25-39th MW) was 861.50 mm. Normal rainfall/week exceeded 50 mm during 12 weeks (25-36th MW) which declined successively for three week (37-39th MW). The coefficient of variation (CY) ranged between 74.3% (25th MW), to 144.7% (39th MW). The rainfall at 50% probability level was well distrturbed during 12 week (25-36th MW)-ranging between 44.5 to 36.3 mm being adequate and sufficient (>20 mm/week) for sorghum crop considering its weekly demand (21-35 mm/week). Typical rainfall patterns representing the situation were defined on the basis of their repetitiveness. Out of four typical rainfall patterns studied the one with lowest rainfall (458.4 mm /season and 30.56 mm/week) fetched the highest yield (865.0 kg/ha) which ensured adequate rains during the various growth stages except maturity. Excessive rainfall (>l00 mm/week) and deficient rainfall <20 mm/week) during every stage were inadequate. Rainfall atleast 30.56 mm/week was most adequate.

​Assessment of Hydrocyanic Acid (HCN) Content during Different Stages of Growth in Johnson Grass (Sorghum helepensis)

Background: Johnson grass (Sorghum helepensis) is not a cultivated fodder crop but it is a wild variety seen on farm bunds after rainfall in which Sorghum vulgare (Gundrijowar) fodder crops were cultivated in kharif season in Saurashtra region of Gujarat state. At different stages of growth, Johnson grass contains cyanogenic glycosides of varying level which liberate hydrocyanic acid in rumen when it consumed by ruminant animals due to rumen microflora (Toxic level of HCN is 20 mg/ 100 gm dry matter). The current study aimed to estimate varying levels of HCN in Johnson grass to keep dairy farmers informed of safe level of HCN for harvesting. Methods: An investigation was carried out at Cattle Breeding Farm, Junagadh Agricultural University, Junagadh, Gujarat for three consecutive years 2013-2015 in kharif season. Non-cultivated (Sorghum helepensis) fodder samples were collected for quantitative HCN concentration from farm bunds nearby eight sown plots of Gundrijowar (Sorghum vulgare) from 15 DAS and sampling were continued at fortnightly intervals till the plots exhibit 25% flowering stage. Result: Result of obtained data in present study revealed that concentration of HCN in Johnson grass in kharif season decreased significantly (p less than 0.05) on attaining 25% flowering stage during the year 2013, 2014 and 2015. It was concluded that Green Johnson grass can be fed to ruminant animals safely at 25% flowering stage.

Efecto de diferentes niveles de evapotranspiración sobre área foliar, temperatura superficial, potencial hídrico y rendimiento en sorgo forrajero

Se estima que para el año 2050 la población mundial alcance los 9.7 billones de habitantes a una tasa de crecimiento lento. Esto representa un panorama grave en cuanto al abasto del agua y a la producción de alimentos. El objetivo del presente trabajo fue determinar el efecto de diferentes niveles de evapotranspiración sobre el índice de área foliar (IAF), temperatura superficial (Ts), potencial hídrico (Yh) y rendimiento en sorgo forrajero (Sorghum vulgare Pers.) bajo riego por goteo. El estudio se llevó a cabo en el verano de 2019 en las instalaciones del Campo Experimental La Laguna en Matamoros, Coahuila, México. Se evaluaron tres niveles de evapotranspiración (ET) (60, 80 y 100%) utilizados para indicar la lámina de riego a aplicar con los tratamientos de riego por goteo y un tratamiento testigo (riego con melgas irrigadas por gravedad). Se utilizaron dos variedades de sorgo forrajero tolerantes a sequía y de alto rendimiento, Súper Sorgo (SS) y Sorgo Silo Miel (SSM). El diseño experimental utilizado fue parcelas divididas en un diseño de bloques completos al azar con cuatro repeticiones. Se observó diferencia estadística significativa (P ≤ 0.05, Tukey) en rendimiento verde y seco en los tratamientos de riego y variedades. Los mayores rendimientos se observaron en los tratamientos de 80 y 100% de ET, en la variedad SSM. La variedad SS presentó sus mejores rendimientos en los tratamientos con cintilla (80 y 100% de ET), ya que con el riego por gravedad el rendimiento disminuyó en un 26%. En general las diferentes láminas de riego afectaron el IAF, Ts, Yh y rendimiento, siendo el tratamiento de 60% el más afectado reduciendo su rendimiento alrededor de un 25%. El volumen de agua aplicado en los tratamientos de riego con cintilla fue de 24 a 39% menor con respecto al aplicado en el riego por inundación.

PLANTAS TÓXICAS DE IMPORTÂNCIA PECUÁRIA NA REGIÃO DE PEROLÂNDIA – GO

Plantas tóxicas de interesse pecuário são as espécies que, quando ingeridas pelos animais domésticos de produção, sob condições naturais, causam prejuízos à saúde ou mesmo a morte. As intoxicações pelo consumo de plantas tóxicas são de grande importância econômica não só por causar a morte do animal, mais também devido a abortos, queda na fertilidade e produção. Este trabalho teve por objetivos fazer um levantamento das principais plantas tóxicas ocorrentes no Brasil central com registros na literatura; comparar com as plantas tóxicas listadas em levantamento realizado com produtores rurais na região de Perolândia; quantificar a presença e relatar as principais ocorrências de intoxicações no rebanho. Foram feitas entre setembro e novembro de 2016, 16 entrevistas, com produtores rurais da região de Perolândia, utilizando questionários sobre as principais plantas tóxicas causadoras de quadros de intoxicação. Os dados coletados foram transformados em porcentagem e expressos em tabelas. Os resultados deste trabalho permitem concluir que de fato as principais plantas de interesse agropecuário do sudoeste goiano são Urochloa spp (Sinonímia: Brachiaria spp), Enterolobium contortisiliquum, Dimorphandra mollis, Palicourea marcgravii, Pteridium aquilinum, Sorghum vulgare, Senna occidentalis, Stryphnodendrum obovatum, Manihot esculenta, Asclepias curassavica, Ricinus communis, Lantana camara. No município de Perolândia, mereceu destaque especialmente Urochloa spp (Sinonímia: Brachiaria spp), Enterolobium contortisiliquum, Dimorphandra mollis que neste trabalho foram as maiores causadoras de quadros de intoxicação no município.

"Effect Of Planting Date And Distance Between Hills On Growth and Forage Yield Of Sudangrass Hybrid (Sorghum vulgare var. sudanense)"

"This study was conducted in the experimental field of Agriculture Faculty, Wasit University (Wasit Governorate Center) in the autumn season 2018, to study the effect of four planting dates (June 25, July 10, July 25 and August 10) and four spacing between hills (10, 15, 20 and 25 cm) on growth and forage yield of Sudan grass Hybrid. The experiment was carried out by using split-plots with R.C.B.D design with three replicates, the planting dates were put in the main plots, and distances between hills were placed in the sub plots. Two cuts were taken from all treatments ,the following traits were studied ,Plant height,, number of tillers per plant, number of leaves per plant, plant leaf area, leaves/stems ratio, and green forage yield. Planting date on 25 July at 1st cutting gave the highest studied characteristics and green yield were 89.452 t. ha-1, Planting date on 25 June at the 2nd cutting gave the highest studied characteristics and gave green forage yield about 86.090 t.ha-1. Planting at 20cm showed a significant effect among the other distances in most growth characteristics at the 1st and 2nd cutting and gave the highest green forage yield were 85.255 and 58.900 t. ha-1. The distance of 20 cm at the date of June 25 gave the highest green yield, which were 93.200 t. ha-1. The interaction between studied factors showed a significant effect on the green forage yield at 1st cutting, the distance of 20 cm at the date of June 25 gave the highest green yield, which were 93.200 t. ha-1, with an increase of 37.67% over than June 25 date, at a distance of 10 cm, the lowest yield of green fodder was recorded at 67.707 t. ha-1 *Part of M.Sc. thesis of the first author"

Remote hyperspectral sensing for the early detection of Melanaphis sacchari Zehntner, 1897 (Hemiptera: Aphididae) infestations in sorghum leaves

This paper aims to study the reflectance signature information of infested and non-infested sorghum leaves (Sorghum vulgare L.) by sugarcane aphid (Melanaphis sacchari) to discriminate infested sorghum. The study treatments were 0 (0 aphids/leaf), 1 (1-20 aphids/leaf), 2 (21-50 aphids/leaf), 3 (> = 51 aphids/leaf), 4 (> = 51 aphids/leaf + visible damage), 5 (abiotic stress) and 6 (> = 51 aphids/leaf + abiotic stress). An Ocean OpticsTM HR4000 spectrometer was used. The multifactor ANOVA and Kruskal-Wallis tests at 95% confidence indicated that the reflectance at 402.95, 528.43, 658.36, 788.13, and 965.14 nm wavelengths have significant differences between treatments and with the control. Also Kernel Discriminant analysis was carried out and the combination of the wavelengths centered at 788.17 and 965.14 nm allows 70 % of correct classification of treatments. The results indicate that it is possible to detect M. sacchari infested sorghum by using the spectral information of some specific wavelengths. This study may enable the research of an aerial sensor to make recommendation maps of application pesticides.

LIBERACIÓN DE Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) Y MANEJO PARA EL CONTROL DE Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) EN CULTIVO DE SORGO

Melanaphis sacchari es una plaga de reciente introducción en México y puede causar hasta 100% de pérdidas al cultivo de sorgo (Sorghum vulgare). La estrategia del manejo integrado de este pulgón incluye el uso de enemigos naturales, por tal motivo, para colaborar en la problemática ocasionada por este insecto, se planteó el objetivo de evaluar el efecto de la liberación de Chrysoperla externa sobre la población de M. sacchari en el cultivo de sorgo en ambiente natural de cultivo e invernadero. La hipótesis es que la densidad poblacional de M. sacchari y el número de plantas de sorgo infestadas es menor al liberar a C. externa. La liberación de C. externa se evaluó en el cultivo de sorgo en condiciones naturales (campo) y condiciones semicontroladas (invernadero). La densidad inicial en campo fue 20 y la final 153.29 ± 44.52 y 568.26 ± 151.87 pulgones por planta en el tratamiento con C. externa y en el tratamiento sin liberación. La diferencia entre los tratamientos fue significativa (p£0.012 y p=0.023). El promedio de plantas infestadas en campo fue menor al testigo 8.71 ± 2.28 y 19.35 ± 4.65. La densidad poblacional en invernadero inició con 15 pulgones por planta y aumentó exponencialmente hasta 10 716 ± 3961, 16 136 ± 1092, 11 819 ± 496, y 20 612 ± 520 en los tratamientos con C. externa y 2 290 680 ± 1693, y 3 632 040 ± 3179 en los tratamientos sin C. externa. El número de plantas infestadas fue menor en los tratamientos con C. externa (139, 221, 128 y 156) que en los tratamientos sin C. externa (3240 ambos tratamientos). Hubo diferencia significativa entre las densidades poblacionales (p£0.001) y entre el número de plantas infestadas (p=0.0001). Por lo tanto, C. externa controla a M. sacchari sólo cuando se combina con el manejo del cultivo. Estos resultados aportan información para el manejo integrado de esta plaga y establecen la problemática de su control debido a su gran capacidad reproductiva.