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The district Toba Tek Singh is located in the center of Punjab province. It occupies 2nd important position in national citrus production after Sargodha, with citrus orchard area of 11412 hectares and annual production of 160758 tons. Citrus productivity in Pakistan, in general, and Toba Tek Singh, in particular, is far below its its potential which could be attributed to several factors but poor soil health and inadequate soil fertility may be considered an important reason. A comprehensive nutrient indexing survey of thirty citrus orchards grown in different parts of district Toba Tek Singh was conducted to evaluate the soil characteristics and plant nutrient status. GPS coordinates of selected sites were recorded prior to sampling. Soil samples were coll ected at 0-20 cm, 21-40 cm and 41-60 cm depth using standard procedure. Five soil samples were collected from each site to get a composite sample for each depth. The leaf samples were collected from the 7-month-old non-fruiting branches of plants around the tree canopy during the month of September, 2022. Five healthy and uniform citrus trees were sampled from each site to get a composite leaf sample. The soil samples were analyzed for pH, electrical conductivity (EC), soil organic matter (SOM) and calcium carbonate (CaCO3). The soil and leaf samples were analyzed for macro and micronutrients. It was found that most of orchard soils of district Toba Tek Singh were moderately alkaline (pH 7.52-8.90), slight to strong calcareous (2-15% CaCO3), non-saline (0.77-3.0 dS m-1 EC) and low in SOM (0.23-1.49%) with low to medium nitrogen (0.01-0.06%) and phosphorus (0.58-10.52 mg kg-1) while medium to high potassium (56.47-315.34 mg kg-1). The sampled soils were low to marginal in boron (0.09-0.72 mg kg-1), copper (0.05-0.59 mg kg-1), iron (0.23-10.75 mg kg-1) and zinc (0.03-1.83 mg kg-1) while adequate in manganese (1.35-26.20 mg kg-1). Leaf analysis revealed that almost 50% orchards were deficient in phosphorus (0.05-0.23%) and potassium (0.40-1.76%), while having low to marginal values of copper (1.96-20.99 mg kg-1), zinc (4.13-31.96 mg kg-1), boron (3.12-95.40 mg kg-1), manganese (42.62- 96.46 mg kg-1) but adequate iron (171-552 mg kg-1). The surveyed orchard soils were mostly alkaline calcareous, deficient in organic matter and having low to moderate macro and micronutrients. [ABSTRACT FROM AUTHOR]

Kinnow (Citrus reticulata), a type of citrus fruit grown in Pakistan, is world-famous due to its unique taste. However, deficiency of nutrients, environmental stresses, and pests and disease attacks are causing low fruit productivity, juice quality, and fruit dropping. In this study, integrated management of hormones and nutrients was performed in orchards with high premature fruit dropping from major citrus-producing areas of Pakistan to improve fruit yield and quality. Thirty trees (10 to 20 y old) were selected from each orchid. Salicylic acid (100 mg L−1 SA), potassium (100 mg L−1 K), zinc (100 mg L−1 Zn), 2, 4-dichlorophenoxyacetic acid (2 mg L−1 2,4-D), indole acetic acid (10 mg L−1 IAA), and their combinations (SA + K, SA + Zn, SA + 2,4-D, SA + IAA, and SA + K+Zn) were foliar applied at the initiation of flowering, fruit formation, and fruit color initiation stages. Each treatment was repeated thrice while water was sprayed for control. The pathological study and soil and leaf nutrient analysis showed that the yield, quality, and citrus fruit dropping were influenced by insect pests, microbial pathogen infestations, and nutrient deficiency. The results indicated that SA + 2,4-D proved most effective in closely enhancing fruits' weight and size, followed by SA + K+Zn. However, the SA + K+Zn showed the highest net photosynthesis and fruit drop control, followed by SA + 2,4-D. [ABSTRACT FROM AUTHOR]