Classification of maize genotype using logistic regression

Characterization of maize plants is among the pre-requested document prior to release to the public in Indonesia. Characterization of maize genotype involves various parameters includes agronomic parameters, yield and yield components. Characterization is generally carried out by professionals because it requires special skills in identifying genotypes based on their specific characters. The objective of the study was to classify the genotypes of corn plants based on the characters of the ear and kernel using a logistic regression model. The research was conducted at IP2TP Bajeng in 2020 by planting 4 genotypes, namely DYM-15, N 79, Mal 03 and G102612. A total of 100 plants per genotype were planted for cob characterization. Data analysis was done by using open-source software, Orange Software. The results indicated that the logistic regression model had a very good performance in classifying maize genotypes with an accuracy of > 98%. The values of the five parameters used to access the accuracy of the model are AUC=1.0, CA=0.99, F1=0.99, precision=0.99, recall=0.99. This value indicates that the use of IT-based tools can correctly classifying genotypes with high accuracy and consistency of results. Thus, digital based model can be integrated with manual selection for fast and precise grading of maize genotypes for maintaining seed quality.

The influence of maize on the rhizosphere eukaryotic community

The microbiota colonizing the rhizosphere contributes to plant growth, productivity, carbon sequestration, and phytoremediation. Several studies address plant-associated bacteria; however, few studies analyze the effect of plant genotype on the eukaryotic community. Here, we analyzed the eukaryotic composition of maize rhizosphere from three different plant landraces and one inbred line grown in the same soil (common garden approach). This experimental design, coupled with 18S rDNA gene amplicon sequencing, allowed us to test the influence of maize and its genotype on the rhizosphere's eukaryotic community. We found that plant growth modified the eukaryotic community in soil, as diversity comparisons between maize rhizosphere and unplanted soil revealed significantly different eukaryotic composition. Various genera of nematodes and fungi, predominantly bacterial feeding nematodes and mycorrhizal fungi among other taxa, were increased in the rhizosphere samples. We also observed that maize genotype differentially shaped the relative abundance of the following fungal families in the rhizosphere: Acaulosporaceae, Aspergillaceae, Chaetomiaceae, Claroideoglomeraceae, Corticiaceae, Mortierellaceae, Trichocomaceae and Trichomeriaceae. Thus, plant genotype has a selective influence on establishing fungal communities in the rhizosphere. This study emphasizes the importance of an integrated consideration of plant genetics for future agricultural applications of microbes to crops.

THE AGRONOMIC CHARACTER AND POTENTIAL YIELD OF 17’S GENOTYPE OF MAIZE

Maize (Zea mays L.) is one of crops that source of carbohydrate than rice. The maize production needs to production goal. The problems is traditional variety haved low yield. This study aims to determine the agronomic character and potential yield of several hybrids maize.. The research method used was randomized completely block design was repeated 3 times. The treatment factor namely hybrid maize genotype. The data obtained were analyzed in theirs diversities by using variace at 5 % level, if there were significant difference, continued by using the least significant increase at 5% level to compared of variety tester. The results shows that hybrid maize genotypes, G2KPW-43, G2KPW-45, and G2KPW-48 haved superiorities in agronomic character and higher potential yield.Key words: genotypes, potential yield, maize

Design of Automated Rainout Shelter to Conduct Experiment on Drought Tolerant Maize Genotype

Uneven and low precipitation areas of Nepal are continuously suffering from drought and received low productivity because of unavailability of suitable drought tolerant maize genotype. An attempt has been made first time in Nepal by constructing an automated rainout shelter with soil moisture based automated drip irrigation system at National Maize Research Program in 2018-2019 to conduct an experiment on drought tolerant maize genotype. The rainout shelters automatically covers the cropping area as soon as the rain sensor received a single drop of precipitation and also if the light intensity decreased to value set in the control panel. Likewise, the soil water level in different treatments were maintained on the basis of the treatment controlled with automatic drip irrigation system set to irrigate at threshold value set in the microcontroller. The complete system had found very useful in determining accurate amount of water required to cultivate drought tolerant maize genotype. We have tested drought tolerant variety RampurSo3Fo8 under 10 level of irrigation and it was determined that 495.2 mm of water is maximum level of water to produce highest yield of 3.32 t/ha whereas 445.6 mm to 247.6 mm of water could can be manage to produce competitive yield without any reduction. An experiment under such kind of infrastructure provide useful information on irrigation management practices required for drought variety in the natural environment. The research output also guides farmers and agriculturist in making Nepalese agricultural more sustainable, mechanized and productive.

EFFECTS OF WATER DEFICIT ON MAZE SEEDLINGS GROWTH TRAITS

Many biotic and abiotic factors affect plant growth and its development. Maize growth usually increased under excess water availability but less tolerant against water deficit stress condition. In this study, we investigated the effects of water stress on the growth and yield of maize. We found that severe water stress during the seedling stage had a greater effect on the growth and development of maize. Three maize varieties (Pak afghoi, Neelum, White corn) were used to find out the effects on growth of plant under drought or water deficit environmental conditions. Different drought stress treatments (Control, 20% irrigation water, 40% irrigation water, 60% irrigation water, 80% irrigation water) were imposed to growing seedlings after germination. The treatments were applied after 4 times each after 7 days interval and data for different morphological traits was recorded each time. The recorded data was pooled and analyzed for analysis of variance to access the significance of results. The ANOVA indicated the differences among five different genotypes and 5 different treatments for all parameters were significant. Tukey’s test indicated that maize genotype White corn was more tolerant while genotype Neelum was more sensitive for drought stress conditions therefore, white corn maize genotype may be helpful for the development of drought tolerance maize varieties and hybrids. Positive and significant correlation was found for shoot length with all other studied traits under drought stress conditions. Treatment control, 80% and 60% irrigation water was less adverse for maize growth while treatment 20% irrigation water highly affected all maize genotypes, therefore maize genotypes may be grow under treatment 60% irrigation water.

GENETIC EVALUATION FOR SEEDLING TRAITS OF MAIZE AND WHEAT UNDER BIOGAS WASTEWATER, SEWAGE WATER AND DROUGHT STRESS CONDITIONS

Cereals grains have feed mankind since their domestication thousands of years ago and remained the most important source of calories for the majority of human population. Wheat (Triticum aestivum L.) and Maize (Zea mays L.) are used as staple food for more than 50% of world population. For evaluation of wheat and maize genotype under biogas wastewater, sewage water and drought stress, an experiment was conducted in the greenhouse of Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan. The treatments of biogas wastewater, sewage water and drought for maize and wheat genotypes were kept as following T1: control (normal irrigation condition) T2 (sewage water 100ml), T3 (biogas wastewater 100ml), T4 (drought 75% (25ml water)), T5 (biogas 150ml) and T6 (sewage water 150ml) respectively). It was observed from the results that the performance of maize and wheat genotypes were highly variable under biogas wastewater, sewage water and drought treatments. The treatment of sewage water (150ml) and drought (75%) were found as the higher toxic treatments of maize and wheat which were predicted as they may cause to decrease in the photosynthetic rate, productivity and growth of plants. The significant correlation was found between root length and shoot length for both of the genotypes. It was found from the results that maize genotype (Raka-poshi) performed better under most of the stress treatments as compared with wheat genotype (Galaxy-2013) while the higher genetic advance and heritability were reported for maize genotype which revealed that the maize may used to grow for higher grain production under biogas wastewater, sewage water and drought stress conditions.

Soil Bioassay for Detecting Magnaporthiopsis maydis Infestation Using a Hyper Susceptible Maize Hybrid

Magnaporthiopsis maydis is the causal agent of severe maize late wilt disease. Disease outbreak occurs at the maize flowering and fruit development stage, leading to the plugging of the plant’s water vascular system, resulting in dehydration and collapse of the infected host plant. The pathogen is borne by alternative hosts, infected seeds, soil, and plant residues and gradually spreads to new areas and new countries. However, no soil assay is available today that can detect M. maydis infestation and study its prevalence. We recently developed a molecular quantitative Real-Time PCR (qPCR) method enabling the detection of the M. maydis DNA in plant tissues. Despite the technique’s high sensitivity, the direct examination of soil samples can be inconsistent. To face this challenge, the current work demonstrates the use of a soil bioassay involving the cultivation of a hyper-susceptible maize genotype (Megaton cultivar, Hazera Seeds Ltd., Berurim MP Shikmim, Israel) on inspected soils. The use of Megaton cv. may facilitate pathogen establishment and spread inside the plant’s tissues, and ease the isolation and enrichment of the pathogen from the soil. Indeed, this cultivar suffers from severe dehydration sudden death when grown in an infested field. The qPCR method was able to accurately and consistently identify and quantify the pathogen’s DNA in an in vitro seed assay after seven days, and in growth-chamber potted plants at as early as three weeks. These results now enable the use of this highly susceptible testing plant to validate the presence of the maize late wilt pathogen in infested soils and to evaluate the degree of its prevalence.