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Jamun plant displays enormous diversity throughout Pakistan, which necessitates its screening, evaluation, and validation to document elite genotypes having better traits for the benefit of the fruit industry and farmers. Surveys were made in natural Jamun habitats across Punjab, Pakistan, and genotypes were marked based on visual diversity of trees and fruits. In total, 60 Jamun genotypes were selected for characterization based on phenotypic and genetic markers. Phenotypic characters related to trees, leaf, and flower along with fruit qualitative traits were assessed in situ. Results revealed significant diversity with high (>25%) coefficient of variance values and the first two components of correspondence analysis exhibited 41.71% variation among genotypes. A strong association was observed among traits like upright tree and round fruit shape (0.74), bluish-colored fruit and pinkish pulp (0.85), and elliptic-shaped fruit with low fruit waxiness (−0.72). Leaves of phenotypically characterized plants were brought to Wheat Biotechnology Lab., University of Agriculture, Faisalabad, Pakistan, where Jamun genotypes were investigated genetically using Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) markers. A total of 132 bands were scored, of which 108 were polymorphic, corresponding to almost 81% polymorphism among collected genotypes. High polymorphism information content values were observed against RAPD (0.389) and ISSR (0.457) markers. Genotypes were compared in relation to genetic markers, which exhibited that almost 86% of genetic variability was attributed to differences among accessions, while 14% of variation was due to differences between collections of different areas. Findings of this study confirmed wide phenotypic and genetic distinctness of Jamun in Pakistan that can aid breeders for marker-assisted selection and germplasm enhancement for future crop improvement programs. [ABSTRACT FROM AUTHOR]

The etiology of shisham (Dalbergia sissoo) die-back has been a subject of considerable scientific debate for hundred years. No single pathogen species is responsible for die-back outbreaks, making shisham die-back challenging to study. Symptoms of the disease include yellowing, the water-soaked appearance of leaves, thinning of leaves and crown, branch die-back (single or whole), bark splitting, gummosis, and lesion development. Symptomatic shisham were sampled from 117 sites across Pakistan. One hundred and ninety-two fungal isolations were made from 1170 shisham samples and were identified as Ceratocystis sp. and Fusarium sp. based on cultural morphology. Koch's postulates were completed using 23 isolates of Ceratocystis sp. and four isolates of Fusarium sp. on three shisham age groups a) 6-12-month-old nursery seedlings growing under greenhouse conditions, b) 1-3-year-old plants growing under natural field conditions, and c) 10-15-year-old tree growing under natural field conditions. Inoculation with Ceratocystis isolates resulted in typical shisham die-back symptoms. Inoculation with Fusarium sp. did not produce any symptoms alone or in combination with Ceratocystis sp. Four fungicides were evaluated for efficacy against Ceratocystis sp. using in vitro tests and field trials. In in vitro test, propiconazole resulted in the highest level of inhibition (88.88%) at day seven, followed by difenoconazole (84.75%), hexaconazole (81.11%), while benzimidazole (77.73%) was least effective against the tested fungus. The efficacy of these fungicides has declined throughout greenhouse trials conducted in this study. Additionally, these fungicides could not prevent tree loss in trees inoculated with Ceratocystis sp. in the field trials. Thus, shisham die-back continues to be of concern in shisham-growing areas in Indo-Pakistan. However, chemical management and continuing research on the epidemiology of this disease may provide a solution. [ABSTRACT FROM AUTHOR]

Dalbergia sissoo is one of the most economically important trees in forestry, agroforestry, and horticulture. This tree species is severely threatened by dieback. Widespread dieback outbreaks and infestations have drastically destroyed billions of D. sissoo trees. Hence, we attempted to resolve the dieback etiology through phylogenomics associated with D. sissoo mortality. The Ceratocystis species was evaluated using morphologically investigated fungal isolates collected from dieback-affected tissue plants. Based on the symptomatology, we have differentiated dieback from Fusarium wilt and concluded that the Ceratocystis fimbriata sensu lato complex is causing shisham dieback in Pakistan. As the Ceratocystis species complex is a cryptic species complex, we used genomics and phylogenetic analysis for deciphering its evolutionary hierarchical order. The pathogen's operational taxonomy was unlocked with the help of phylogenomics, and it was discovered that isolates from D. sissoo represent a species distinct from the other species in the C. fimbriata sensu lato species complex. The name Ceratocystis dalbergicans sp. nov. has been given to the fungus causing dieback disease in D. sissoo. [ABSTRACT FROM AUTHOR]

Phoenix dactylifera L. (Date palm) is one of the leading perennial fruit crops regarding its nutritional profile, medicinal significance, excellent yields, long life, and high adaptability to diverse climatic conditions of semi-arid and arid regions globally. Eleven major palm-growing districts of Punjab, Sindh, and Khyber Pakhtunkhwa were surveyed for wilt disease assessment on date palms. The date palm plantation was highly affected with Fusarium wilt diseases with 55%, the incidence in Khairpur (Sindh province), followed by Bahawalpur at 47.4% (Punjab Province) and 45% in Dera Ismail Khan (KPK province). Disease severity was recorded as 65% in Khairpur, 55% in Bahawalpur, and 50% in Dera Ismail Khan (Sindh, Punjab, and KPK, respectively). Sixty-three Fusarium isolates were obtained from three hundred and eighty (380) diseased samples, and thirty isolates randomly selected out of 63 were studied for morpho-cultural and microscopic characterization. Morpho-cultural characters, i.e., colony pigmentation, growth pattern, conidia (macro and microconidia), shape, apical cell shape, and phalidies studied, coinciding with typical characteristics of Fusarium oxysporum. Twenty isolates of the Fusarium population were subjected to the ITS region sequence data-based phylogenetic network. The Neighbor net algorithm computed an unrooted phylogenetic network displayed as four branched genetic network that depicted the division of twenty fungal isolates into four groups. F. oxysporum (FMB-FO-PD-011) inoculated onto healthy symptomless detached date palm leaves, seedlings, and suckers under controlled and field conditions showed typical wilt disease symptoms. Hence this study proved that F. oxysporum is the potential cause of date palm wilt in Pakistan. [ABSTRACT FROM AUTHOR]

Shisham (Dalbergia sissoo) dieback disease has been a subject of great economic importance for the last few decades in South Asian countries. This disease prevails across the shisham growing geographical regions in these countries. Shisham dieback disease has been highlighted as a national forest problem in Pakistan. In this investigation, major shisham plantations of Pakistan were targeted for disease surveillance and monitoring. The extent of shisham dieback disease at different age classes of shisham plantations was also quantified. Surveillance data revealed, that shisham dieback disease is present in all surveyed shisham growing areas, including in areas where mild to no shisham dieback had been reported previously. A significant correlation was observed between different environmental variables (temperature (T), rain fall (RF), and relative humidity (RH) and disease development at (P < 0.01). T has negative correlation with RF (r= -0.793) and RH (r= -0.867). Infection prevails in different ecological zones depicted that environment has a minor role in disease development. Shisham dieback disease symptoms gain a seasonal peak from mid-February to end-March and mid-August to mid-October. Plants belonging to different age classes were exhibited different levels of disease incidence (20.95-28-2%). These findings will guide policy making and breeding programs with the goal of successful management of the shisham dieback disease and sustainable production of shisham in Pakistan. [ABSTRACT FROM AUTHOR]

Huanglongbing (HLB) is causing destruction in citrus all over the world. Control of this disease is mendatory to save the citrus industry. Asian citrus psyllid (ACP), the natural vector of HLB causing bacterium is present in abundance in citrus orchards of Punjab, pakistan. Rearing of ACP was conducted in this study for the management strategies of HLB. Citrus orchards of Faisalabad district of Punjab, Pakistan were surveyed for HLB diagnosis and acquisition of ACP from HLB positive citrus trees for ACP rearing in controlled conditions of growth room. ACP was successfully reared at 26±2 °C temperature and photoperiod of 13:11 (Light : Dark) and Candidatus Liberibacter asiaticus was detected by conventional PCR in the plants used for ACP rearing. PCR results confirmed the presence of Candidatus Liberibacter asiaticus with discrete bands having amplicon size of 1160bp, 800bp and 700bp for primer pairs OI1/OI2c, OI2/23S1 and A2/J5, respectively. [ABSTRACT FROM AUTHOR]