Tasneem Khaliq

Application of CSM-CERES-Maize model in optimizing irrigated conditions:

Maize is one of the main cereal crops in Pakistan with sensitivity to drought at various developmental stages known to influence the yield. The impact of variable weather conditions on maize yield can be analyzed with crop simulation models. The CSM-CERES-Maize model has been widely used to assess irrigation strategies for maize. This research was conducted to test the CSM-CERES-Maize model for its ability to accurately predict maize biomass and grain yield under water limiting and non-limiting conditions in semiarid conditions. Four growth stage-based irrigation treatments and two potential soil moisture deficit-based treatments were defined. During model calibration, the simulated maximum leaf area index (LAI), total dry matter (TDM), and grain yield were all within 10% of observed values. During model evaluation, there was generally satisfactory agreement between observed and simulated values for two hybrids (Monsanto-919 and Pioneer-30Y87) with the model showing variability of −17.9–20.0%, −9.2–14.3%, and −19.6–19.9% for maximum LAI, TDM, and grain yield, respectively, for the two hybrids among various treatments. The CERES-Maize model was useful in providing information to decision-making regarding diverse irrigation regimes at the farm level in a semiarid environment.

Effect of organic and inorganic fertilizer on maize hybrids under agro-environmental conditions of Faisalabad-Pakistan

crop is the 3 rd cereal crop of Pakistan after wheat and rice. According to the economic survey of Pakistan, it is cultivated on the area of approximately, 1.11 million hectare and production from this area was 4.04 million tone s. A field experiment was conducted at Agronomic Re search Area, University of Agriculture, Faisalabad-Pakistan to examine the effect of organic and inorganic fertilization on maize productivity. The experiment was laid out in Randomized Complete Block De sign (RCBD), with four replications. Two maize hybrids were used in this experiment. The results showed that maize yield and its component such a s cobs per plant, cob length, number of grains per cob, 1000 -grain weight were maximum when the plots were fertilized at 100 kg N ha -1 as urea + 100 kg N ha -1 as poultry manure. Further re search is desired to inve stigate maximum yield by using organic source of fertilizer than inorganic source of fertilizer to avoid lethal effects on human health created by inorganic fertilizers.

Influence of Nursery Management and Seedling Age on Growth and Economic Performance of Fine Rice

Seedling vigor is the basic component of the transplanted rice, which depends on its growing environment and proper age. Thus the influence of nursery management and seedling age was evaluated after transplanting 10, 20, 30, and 40-days older seedlings raised by using seed rate (high and low) and nitrogen (N) (with and without) in rice growing season 2008 and 2009. Study revealed that 10-days older nursery seedlings, irrespective to nursery-bed treatments, showed accelerated growth start after transplanting in main field while at later stages significant interaction was observed. Transplanting of 20-days older fertilized seedlings grown at low seeding density at nursery-bed resulted in similar growth performance as in younger. Maximum net-benefit (45111, 44402 Rs. ha−1) was recorded with transplanting 10-days older nursery seedlings while the fertilized seedlings grown at lower seeding density recorded highest net-benefit (37908, 36780 Rs. ha−1) in both the years.

Inheritance pattern of vital post-emergence morphometric and meristic traits of spring wheat

programme revealed that the traits like plant height, flag leaf area, number of tillers per plant, peduncle length and number of grains per spike were ruled by partial dominance with additive type of gene action. These results recommend that the selection in early segregating generations may lead to fairly good improvement in these characters. Some other traits like spike length, spike density and grain yield per plant were governed by over-dominance type of gene action which recommend delayed selection for efficient breeding of these traits. Epistasis was found absent for all the characters studied. These results lead us to the conclusion that the study of different inheritance patterns plays key role in designing comprehensive breeding programmes. Key words:

Recognizing production options for pearl millet in Pakistan under changing climate scenarios

Abstract Climate change is making the lands a harsher environment all over the world including Pakistan. It is expected to oppose us with three main challenges: increase in temperature up to 2–5°C (heat stress), increasing water stress and severe malnourishment due to climate change. It has been foreseen that there will be a 10% increase of dryland areas with climate change in the world, with more variability and incidences of short periods of extreme events (drought and heat stress). Pearl millet is a hardy, climate smart grain crop, idyllic for environments prone to drought and heat stresses. The crop continues to produce highly nutritious grain sustainably, thereby encouraging the fight against poverty and food insecurity due to its resilience. The crop is more responsive to good production options (planting time, planting density, inter/intra row spacing, nitrogen application and irrigation). It has high crop growth rate, large leaf area index and high radiation use efficiency that confers its high potential yield. In most of the cases, pearl millet is remained our agricultural answer to the climate calamity that we are facing, because it is selected as water saving, drought tolerant and climate change complaint crop. In view of circumstances, pearl millet cultivation must be retrieved by recognizing production options in context to changing climate scenarios of Pakistan using crop modeling techniques.

IMPACT OF VARIOUS IRRIGATION LEVELS ON GROWTH, YIELD AND WATER USE EFFICIENCY OF WHEAT AT VARIABLE TEMPERATURES

Water and heat stress are among the principle stresses affecting the productivity of cereals worldwide. This study was conducted at the Agronomic Research Area, University of Agriculture, Faisalabad during 2010-2011 to check the influence of various irrigation regimes on growth, yield and water use efficiency of wheat at variable temperatures. The treatments were comprised of three irrigation levels: I

Performance of four crop model for simulations of wheat phenology, leaf growth, biomass and yield across planting dates

Robustness of four wheat simulation model were tested with 2-year field experiments of three cultivars across a wide range of sowing dates in two different climatic regions: Faisalabad (semi-arid) and Layyah (arid), in Punjab-Pakistan. Wheat growing season temperature ranged from -0.1°C to 43°C. The wide series of sowing dates was a unique opportunity to grow the wheat in an environment which temperatures varies from -0.1°C to 43°C. The CERES-Wheat, Nwheat, CROPSIM-Wheat and APSIM-Wheat model were calibrated against the least-stressed treatment for each wheat cultivar. Overall, the four models described performance of early, optimum and late sown wheat well, but poorly described yields of very late planting dates with associated high temperatures during grain filling. The poor accuracy of simulations of yield for extreme planting dates point to the need to improve the accuracy of model simulations at the high end of the growing temperature range, especially given the expected future increases in growing season temperature. Improvement in simulation of maximum leaf area index of wheat for all models is needed. APSIM-Wheat only poorly simulated days to maturity of very and extremely late sown wheat compared to other models. Overall, there is a need of improvement in function of models to response high temperature.