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Indian jujube (Ziziphus mauritiana Lamk.) is a drought tolerant fruit crop and well adapted to sub-tropical to tropical climates. Seasonal pruning in jujube is essential to sustain the plants as productive with quality fruits because flowers and fruits are borne on young shoots of current season’s growth. This experiment was initiated and accomplished during 2016-18 to assess appropriate extent of pruning in various cultivars of Indian jujube with regard to productivity and fruit quality. Four cultivars of jujube i.e., Dehli Sufaid, Pak White, Umran and Alu Bukhara were subjected to four pruning levels i.e. no pruning, 25%, 50% and 75% pruning by removing unproductive, over-crowded secondary and tertiary branches leaving 3/4 (light), 1/2 (medium) and 1/4 (severe pruning) portion of branch intact with main limb, respectively. Experiment was laid out in randomized complete block design with three replications and statistically analysed in 2-factors factorial way. Pak White initiated new growth earlier (39 days), produced maximum branches per plant (77), shoots (15), panicles (63) and fruits (90) per branch, heavier (38 g) and bulky fruits (44 cm3), with minimum fruit drop (13%), higher yield (184 kg) per plant and fruits carrying the maximum pulp ratio (90%), total soluble solids (16 °Brix), vitamin C content (121 mg /100 g pulp) and total sugars (5.7%). Fifty percent pruning level proved more judicious in all jujube cultivars. Pak White performed the best when subjected to 50% pruning level for all the parameters under study as calculated by interaction between two factors.

Application of green manures substitutes use of chemical fertilizers, improves soil health, prevents soil degradation also ensures food security. Two years’ field experiment was laid out to determi...

Mango being one of the most important fruit crops in Pakistan is facing a serious issue of malformation. If it is not treated, it renders great economical losses. Samar Bahisht Chaunsa is an excellent quality exportable cultivar of mango, but it is also the most vulnerable to inflorescence malformation. Therefore, the present study was carried out to address the malformation issue in mango cv. Samar Bahisht Chaunsa during 2016-18. The treatments comprised of pruning during March, pruning during April, pruning during March along with spray of Topsin-M @ 2 g L-1, pruning during April along with spray of Topsin-M @ 2 g L-1 and leaving plants un-pruned without spray as control. The tree branches were pruned up to 20 cm beneath the malformed inflorescences. Data on number of days taken to initiate growth, number of emerged flushes, number of bloomed flushes and number of malformed inflorescences were recorded. Pruning during March in combination with 2 g L-1 Topsin-M spray significantly affected all the parameters. The minimum number of days (37) taken for growth initiation, the highest number of emerged flushes (3.5) as well as bloomed flushes (3.2) along with the least number of malformed inflorescences (1.4) were recorded for the aforementioned treatment. Un-pruned and non-sprayed branches (control) did not initiate growth.

Monsoon crop of guava is hit by fruit fly during July-August that results into huge loss to the producers. Spray of urea and Naphthalene acetic acid (NAA) is used to drop flowers and fruits of monsoon crop to get higher yield of winter crop. This study was carried out at Fruit Orchard of Horticultural Research Station, Bahawalpur during 2015-2017 to determine the optimum concentration of selected chemicals to drop flowers and immature fruits of monsoon crop. Plants with distilled water spray were treated as control (T1). Other treatments included urea @ 5% and 10% (T2 & T3), NAA @ 0.05 and 0.1% (T4 & T5) as 1st spray and repeated the same spray after fortnight, combination of urea (5%) as 1st spray followed by NAA (0.05%) as 2nd spray (T6) or urea (10%) 1st spray followed by NAA (0.1%) as 2nd spray (T7). Consolidated means of parameters over two years’ study indicated that the highest fruit yield (68.6 kg/plant), the maximum weight per fruit (168.3 g), number of fruit/plant (375), pulp content (55.5%), pulp thickness (1.05 cm), total soluble solids (14.3 °Brix), ascorbic acid content (176.7 mg / 100 g pulp) and total sugars (7.6%) were obtained as a result of highest flower drop (96.7%) and fruit drop (76.9%) with lowest fruit set (2.9%) from non-target monsoon fruiting in response to 0.1% NAA (T5) sprayed twice at fortnight interval, proceeded after the application of 0.05% NAA two spray fortnightly (T4). The plants under control remained at bottom with respect to parameters i.e. flower and fruit drop, at top with highest fruit setting in monsoon crop that led to the lowest yield of winter crop.

Pomegranate is a drought tolerant fruit crop and is well adapted to sub-tropical and tropical climates. Fruit cracking is a major disorder in pomegranate which causes significant economic losses. In the present work, effect of foliar application of boric acid (0.05%), potassium nitrate (1.0%) and magnesium sulphate (1.0%) alone or in combinations was investigated to manage fruit cracking and improve fruit yield and quality of pomegranate cv. Golden. First treatment (foliar spray) was applied one month after fruit setting (April) and repeated twice during May and June each year. Application of foliar sprays affected fruit yield and quality positively. The maximum number of fruits per plant (254), average fruit weight (192 g), yield per plant (58.3 kg), number of arils per fruit (592), juice content (41.1%) as well as the minimum fruit cracking (3.9%) were recorded when 0.05% boric acid, 1% potassium nitrate and 1% magnesium sulphate were applied in combination. Fruit size and total soluble solids (TSS) of fruit juice were not affected by the applied treatments. Thus, combined application of boric acid, potassium nitrate and magnesium sulphate could be recommended for reducing fruit cracking and improving yield and quality of pomegranate fruits under semi-arid conditions of Southern Punjab, Pakistan.

In this paper, a novel array structure exploiting coprime arrays is proposed, which comprises the translocation of one subarray and axis rotation with a compression of another subarray to produce a larger number of consecutive lags. This composition is named CATARCS, which stands for coprime array with translocated and axis rotated compressed subarrays. The scheme offers consecutive co-array lags in remarkable number $4MN-1$ by using only $2M+N-1$ number of sensors attaining higher degrees of freedom than the state of the art, where $M$ and $N$ are coprime with congenial interelement spacings. However, a very few holes still exist in the co-array, which can be filled up through interpolation. In this paper, the iterative power factorization (IPF) algorithm has been demonstrated as a tool for incremented-rank-IPF matrix recovery which is unostentatious. No extra tuning parameter is required for this approach and several undesired issues of other techniques can be reconciled by this. The main contribution of this paper is suitable modification of array geometry arrangements to increase consecutive lags and to interpolate via IPF, which is used first time for direction of arrival (DOA) estimation in order to exhibit better performances in terms of detecting and resolving a larger number of sources by enhancing resolution. Later, DOA estimation can be achieved by performing multiple signal classification (MUSIC) algorithm. Simulation results validate its effectiveness by achieving lower cost, faster, and accurate DOA estimation even in lower angular separation of sources compared with other techniques like spatial smoothing MUSIC, co-array the least absolute shrinkage and selection operator, spline, iterative co-array array interpolation, and Toeplitz completion.

In this paper, a novel array structure exploiting coprime arrays is proposed which can be very proficient to determine the number of consecutive lags in proportion with the number of array elements. The proposed method comprises novel array structure by configuring three subarrays positioned in alignment with some prescribed values. By increasing array elements in third subarray while keeping other subarrays fixed, explicit number of consecutive lags could be obtained proportionately. The proposed method offers maximization of consecutive lags in remarkable number by calculating the fourth order difference co-array unifying interpolation. The forth order difference co-array is achieved by exploiting the second order difference co-array twice. The consideration of third subarray in addition with two coprime subarrays leads to a novel array structure which can significantly enhance degrees of freedom. An effective interpolation technique nuclear norm minimization is considered to fill the holes subsisting in the virtual co-array in order to exploit full virtual co-array length. This interpolation method uses convex framework which is trackable and very simple to implement yielding a freedom of fixing any predefined extra tuning parameter. The proposed method in this paper is named as VEFODCI which stands for virtual extension of coprime arrays by exploiting fourth order difference co-array with interpolation. The sparse Bayesian learning is used for direction of arrival (DOA) estimation exploiting the proposed novel array structure by imposing interpolation to fill the holes. The array geometry of sensor distributions proves that the proposed method is less susceptible from mutual coupling effect. The simulation results stipulate that the proposed method is performing DOA estimation accurately even in lower angular separation of sources by achieving larger number of consecutive lags than the state of the art.