Rizwan Rafique

Progressive warming of the grape growing regions has reduced the land capability for sustainable grapevine production and the geographical distribution of grapes. Bud burst, blooming, berry set, veraison, and harvest are the key phenological stages of grapevine, and are crucial for managing vineyard activities. The objective of this study was to evaluate the effect of seasonal temperature variability on the timing of key phenological stages of table grape cultivars in a new emerging viticulture region, i.e., the Pothwar region of Pakistan. Phenological stages of four table grape cultivars were recorded during two consecutive growing seasons at two locations. All phenological stages were attained earlier for the relatively warmer location, i.e., Chakwal. Similarly, the length of the growing season from bud burst to harvest was 15 to 21 days longer for the 2020 growing season than for the 2019 growing season, which corresponds to the inter-annual temperature variability. Moreover, the grapevine cultivars showed a distinct response for each growth phase; cv. Perlette matured earlier while cv. NARC Black was the last to ripen. Despite the large variability in the length of the active growing period from bud burst to harvest, accumulated growing degree days (GDD) varied only in a narrow range, i.e., 1510–1557 for cv. Perlette, 1641–1683 for cv. King’s Ruby, 1744–1770 for cv. Sugraone, and 1869–1906 for cv. NARC Black. This implies that seasonal temperature variability using GDD is a better indicator for the phenology of table grape cultivars compared to regular time. It is clear from the results from this study that the variation in phenological responses of table grape cultivars due to temperature differences necessitates genotype and site-specific vineyard management.

Phenolics compounds in grapes contribute to berry and must color, organoleptic properties, nutritional value, antioxidant properties and provide protection against environmental challenges. Climate change has place mammoth challenges for the viticulture industry in different viticulture regions. Environmental variables determine to the greater extent, suitable grapes varieties for fresh as well as premium quality wine production. Grape berry composition is particularly affected by heat, drought, and intensity of solar irradiation. It is expected that climatic extremes will have an adverse effect on berry quality traits such as phenolic compounds in different grape cultivars. Polyphenols particularly anthocyanins decrease at elevated temperature, similarly flavanols levels increase with better exposure to solar radiation. Water availability is crucial for better vine growth and good production, however modest water stress particularly near veraison, upregulates the activity of key enzymes of the phenylpropanoid and flavonoid pathways. Therefore, it is important to know that how and when phenolic substance accumulate in berries and how various cultivars respond. This review elaborates the effect of weather conditions on biosynthesis of different phenolic compounds in grapes. Berry phenolic substances e.g., total phenolic compounds (TPC), total anthocyanins (TAC) and total flavonoid contents (TFC) synthesis is strongly regulated under the influence of environmental conditions during growing season. In this chapter we, shall focus on accumulation of phenolic compounds in grapevine in relation to climatic variations.

Grasses are of great importance for sustainable food production in different ecosystems. Leaf anatomical studies of grasses are the indicator for adaptation of grasses in different areas of the world. The present research study was conducted to evaluate the diversity of leaf anatomical adaptations in different grass species from Faisalabad region in Pakistan. Thicker epidermis in Paspaledium flavidium, Setaria pumila and Eleusine indica is the adaptation to survive under water stressed environments such as drought and salinity. Larger cortical cell area in Setaria verticillate, Digitaria sanguinalis and Eleusine indica is a sign of their wide distribution in a variety of environmental conditions. Eragrostis tenella and Desmostachya bipinnata with significantly larger vascular bundle is the better adaption to a variety of environments. Different species of grasses showed variable responses in their anatomical characters. These variations help to evaluate the adaptation of grasses in varying climatic conditions and their ability to tolerate abiotic stress (i.e., drought and salinity) which are common in this region in natural habitats of grasses.

Aim of study: A field experiment was executed, under rainfed conditions from 2014-15 to 2017-18, to study the role of cowpea (Vigna unguiculata L.) in rainwater harvesting to enhance the wheat (Triticum aestivum L.) yield.Area of study: Rain-fed area of Pothwar region, Punjab, Pakistan.Material and methods: We designed three treatments (T1: control; T2: cowpea grown after conventional tillage and incorporated into soil to act as “green manure”; and T3: grown without any tillage practice, cut with sickle and spread as “mulch”). The effect of these treatments on soil moisture conservation was studied against conventional farmer’s practice, wherein no host crop is grown before wheat sowing.Main results: Available soil water remained highest in T2 during first three years when sufficient rainfall was received contrary to fourth year with low rainfall. The results revealed that cowpea biomass of 15.2 t/ha and 13.72 t/ha, from T2 and T3 respectively, were produced during 2015 corresponding to 213 mm rainfall. Whereas, these quantities increased to 25.69 t/ha and 24.29 t/ha during 2017 with 387 mm of rainfall. The study revealed that net income from wheat crop under T2 was Rs 13000 and Rs 9000 per hectare higher than that of control during the first two years respectively. Contrarily, net income from T2 was found negative and benefit-cost ratio reduced to 0.79 when very low rainfall was received during the last year.Research highlights: Use of cowpea as green manure gave maximum net return if sufficient rainfall is received during decomposition of cowpea and hence recommended for in-situ rainwater harvesting.

A field experiment was conducted to study the effect of micronutrients, zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), boron (B) and a commercial fritted micronutrient product called Zarzameen, on the yield and the yield components of wheat (Triticum aestivum L.), in the Peshawar valley, Pakistan. Different combinations of Zn, Cu, Fe, Mn, B, and Zarzameen were applied at the rate of 4.0, 2.0, 5.0, 2.0, 1.0 kg ha− 1 and 1.0 kg ha− 1, respectively, along with a basal dose of 100 kg ha− 1 nitrogen (N), 75 kg ha− 1 phosphorus (P) and 50 kg ha− 1 potassium (K). The fertilizer treatments (macro- and micronutrients) increased wheat dry matter, grain yield, and straw yield significantly over an unfertilized control. Soil tests for B and Zn were increased both at boot and harvesting stage, and Fe at boot stage, with the addition of micronutrients. Plants without B had showed classical B deficiency symptoms at grain formation stage, but not at vegetative stage. Boron concentration in the dry matter of wheat pla...