Muhammad Akbar Anjum

Evaluation of genetic diversity in Pyrus germplasm native to Azad Jammu and Kashmir (Northern Pakistan) revealed by microsatellite markers

Medicinal plants are important elements of indigenous medical system that have persisted in developing countries. Many of the pharmacological principles currently used as anticancer agents were first isolated from plants. However, some important anticancer agents are still extracted from plants because they cannot be synthesized chemically on a commercial scale due to their complex structures that often contain several chiral centers. The aim of this study was to test different extracts from the leaves of Moringa or drumstick tree ( Moringa oleifera ) for activity against leukemia and hepatocarcinoma cells in vitro . The extracts could kill majority (70 - 86%) of the abnormal cells among primary cells harvested from 10 patients with acute lymphoblastic leukemia (ALL) and 15 with acute myeloid leukemia (AML) as well as a culture of hepatocarcinoma cells (75% death), but most significantly by the hot water and ethanol extracts. In conclusion, M. oleifera may have potential for use as source of natural treatment for diseases such as cancer.

DNA methylation — an essential mechanism in plant molecular biology

DNA methylation is a common phenomenon in plants. In plant genomes, its level is comparatively lower than that of animal genomes. It is involved in gene regulation and controls many development pathways. Methylation status of particular DNA sequence controls the potential for transition from vegetative to reproductive growth. It is believed that fully methylated elements are genetically and transcriptionally silent, however, some methylated genes may also be expressed. While hypomethylated elements are active and partially methylated elements, designated programmable, exhibit a variety of development expression programmes during plant development. DNA methylation plays an important role in the evolution of plant species through alloploidy or polyploidy. The methylation pattern in parental plants is highly heritable which is of great interest for plant breeders. DNA methylation also plays an important role in genome defense system by inactivating and methylating the invasive DNA sequences. A methylated sequence may suppress gene expression in other sequences. The generation and breeding of transgenic plants becomes complex due to inactivation of transgenes and instability of their expression. The pattern of methylation is maintained by methyltransferase through DNA replication. Several methods are in use to detect methylated nucleotides motifs that may help in identification of some essential genes.

Exogenous Application of Growth Enhancers Mitigate Water Stress in Wheat by Antioxidant Elevation

The present study was conducted to investigate the response of two wheat cultivars (AARI-11 and Millat-11) to a foliar application of four growth enhancers which include: {H2O (water), MLE30 (moringa leaf extract), KCl (potassium chloride), and BAP (benzyl-amino purine)}, within the six irrigation water-regimes which are applied at the various critical growth stages such as crown root initiation (CRI), tillering (T), booting (B), and heading (H). Irrigation water-regimes include: CRI+T+B, CRI+T, CRI+B, T+B, T+H, and control (CRI+T+B+H). The growth enhancers i.e., H2O, MLE30 (1:30), KCl (2%), and BAP (50 mg L−1) were applied @ 500 L ha−1 at tillering and heading stages. The results demonstrated some increased quantities of both enzymatic (superoxide dismutase, peroxidase, catalase) and non-enzymatic (ascorbic acid, phenol) antioxidants in leaves of AARI-11 when MLE30 was applied under T+B and T+H irrigation water-regimes. Similar results were also observed in the case of leaf chlorophyll “a” and “b” and K+ contents in both cultivars under control, T+B and CRI+T+B irrigation water regimes. AARI-11 produced the highest biological and grain yield, due to the application of MLE30 and BAP under control, CRI+T+B, T+B, and T+H irrigation water-regimes. However, KCl lagged behind among the treatments set for both cultivars under all the irrigation water-regimes. Foliar spray of MLE30 remained prominent growth enhancer and stresses mitigating agent under water deficit conditions particularly under T+B and T+H irrigation water-regimes. Moreover, economic analysis indicated that the foliar application of MLE30 is a cost effective and environment friendly strategy for the maximum yield and income.

Effect of protoplast source and media on growth and regenerability of protoplast-derived calluses of Solanum tuberosum L

Freshly isolated mesophyll and suspensions-cell protoplasts of S. tuberosum cvs. Desiree and Maris Piper were cultured in different media i.e. modified MS, V-KM and MS-KM. Protoplast plating efficiencies were higher in MS-KM medium. Resulting protoplast-derived calluses were transferred either onto the medium of Bokelmann and Roest (1983) or that of Lam (1977) for shoot regeneration. Calluses derived from mesophyll cell protoplasts differentiated about 2 weeks earlier than calluses derived from suspension-cell protoplasts. Shoot initiation was also about 2 weeks earlier from calluses subcultured onto the former medium as compared to the latter.

Effect of Various Factors on the Efficiency of Agrobacterium-Mediated Transformation of Grape (Vitis vinifera L.)

The present investigation was conducted to study the effect of inoculation time, cocultivation period and various concentrations of hygromycin and kanamycin on genetic transformation of grape (Vitis vinifera L.) cv. Kings Ruby through Agrobacterium tumefaciens. The Chitinase gene (for fungal resistance) and GUS gene (for phenotypic expression of transgenic) were introduced in the embryogenic calli developed from leaf discs, through Agrobacterium strain LBA4404 harboring plasmid pBI121 nptII as selectable marker for GUS gene and hptII for Chitinase gene. Regarding transformation efficiency rate, 10 minutes inoculation period with bacterial suspension showed the highest transformation efficiency rate i.e. 2.83% with Chitinase gene and 2.5% with GUS gene. Infected calli with Chitinase gene and GUS gene co-cultivated for 2 days showed the maximum transformation efficiency of 2.75% and 3.25%, respectively. For elimination of excess bacteria, cefotaxime treatment (300 mg L−l) showed the highest survival rate of 3.16% for Chitinase gene and 2.5% for GUS gene. The maximum i.e.2.83% transformation efficiency rate was achieved at 10 mg L−l of hygromycin for selection of transformed calli. The highest 2.25% transformation efficiency was yielded when kanamycin was used at the rate of 100 mg L−l. Five out of 8 calli showed positive expression with 62.5% transformation efficiency through histochemical GUS assay. Present results may be helpful in improving genetic transformation efficiency of grape through Agrobacterium tumefaciens against fungal diseases and reduce the use of fungicides.

Role of plant growth regulators in preservation of Pyrus germplasm in vitro

In vitro established shoots of nine pear genotypes namely; Khurolli, Bagugosha, Pathar nakh, Desi nakh, Kotharnul, Btangi, Frashishi, Kashmiri nakh, and Raj btung, were preserved by lowering concentration of growth regulators [(0.00, 0.25 or 0.50mg l -1 6-benzyaminopurine (BAP) or adding growth retardants, 10 mg L-1 Alar (diaminazide or B-9), or abscisic acid (ABA)] in the culture medium. The cultures were assessed for their survival and regenerability percentages after 3, 6, 9 and 12 months of storage. The genotypes differed significantly for survival and regeneration percentage. The culture medium supplemented with 0.50 mg L -1 BAP was comparatively more effective and resulted in higher survival rate and re-growth after transferring onto the fresh medium. Storage for short duration (3 months) resulted in significantly higher survival and regeneration rates than other storage periods. As storage period was prolonged, survival and regenerability of shoots progressively decreased. Overall results indicated that the shoots of Desi nakh had the highest survival (73.33 %) and Pathar nakh showed the maximum regenerability (67.66 %) when cultured on the medium supplemented with 0.50 mg L -1 BAP and stored for 3 months. However, no shoots of Kotharnul survived when cultured on the medium without any growth regulator and kept for 12 months. Key words : Growth retardants, in vitro preservation, pear genotypes, slow growth.

Cytology of Potato Callus Cells in Relation to their Frost Hardiness

Structure of callus cells of frost-sensitive and frost-tolerant Solanum species and a frost-tolerant cell line (D20-1), selected from S. tuberosum cv. Desirée callus, was studied. Like frost-tolerant species S. commersonii, cells of the frost-tolerant cell line contained starch grains in their plastids. The cells of this frost-tolerant line also possessed an increased number of microbodies containing protein crystals which suggests the involvement of proteins in frost tolerance but the mechanism may differ from that in frost-tolerant species.

Foliar treatment with Lolium perenne (Poaceae) leaf extract alleviates salinity and nickel-induced growth inhibition in pea

Abstract The plants of pea (Pisum sativum L.) were grown under NaCl and/or NiCl2 stress, to comparatively evaluate stress-mitigating effects of pure proline and naturally proline-enriched Lolium perenne (L.) aqueous leaf extract. Both stress factors (salinity and nickel) significantly reduced plant biomass, chlorophyll content, photosynthetic activity, stomatal conductance, intercellular carbon dioxide (CO2) level, number of stomata, stomatal size, water-use efficiency, relative water content (RWC), and the membrane stability index (MSI). However, the proline and glycinebetaine contents, lipid peroxidation, electrolyte leakage, and activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase) were significantly increased. Exogenously applied proline and Lolium perenne (LP) leaf extracts significantly overcame the nickel and/or salinity-induced toxic effects on growth, RWC, and various photosynthetic attributes. However, follow-up treatment with proline and LP-leaf-extract detoxified the stress caused by NiCl2 and/or NaCl, by suppressing lipid peroxidation and electrolyte leakage, accelerating the antioxidant enzyme activities, and improving the MSI, leaf/root proline, and glycinebetaine contents. LP-leaf-extract proved to be better than pure proline for improving growth, gas exchange parameters, osmolytes, RWC, and antioxidant enzyme activities. As LP-leaf-extract was enriched with a substantial amount of proline along with many other essential osmoprotectants, it was found to be as effective as pure proline in ameliorating growth, some major physiological attributes, and non-enzymatic and enzymatic antioxidant activities in the pea, under nickel and/or salinity stress. Thus, it could be used as an alternative inexpensive source of proline, to be used as a mitigating agent for protecting plants against the deleterious effects of nickel and/or salinity stress.

ASSESSMENT OF ADVANTAGES OF PEA AND NON-LEGUME WINTER VEGETABLE INTERCROPPING SYSTEMS THROUGH COMPETITION AND ECONOMIC INDICES

Intercropping is considered as a promising system having multi-dimensional advantages such as improved yield on sustained basis, effective use of land and other resources and reduction in cost of production. The present study was carried out using pea and three non-legume winter vegetables, i.e. garlic, turnip and cauliflower, by planting as sole crops and in pea–garlic, pea–turnip and pea–cauliflower intercropping systems to determine the competition among these vegetables and economics of each intercropping system. The intercropping systems were assessed on the basis of existing competition and economic indices such as land equivalent ratio (LER), relative crowding coefficient ( K ), aggressivity ( A ), competitive ratio (CR), actual yield loss (AYL), intercropping advantage and monetary advantage index (MAI). Yields of individual vegetables were higher when grown as sole crops compared with their intercropping with pea. Harvest index for pea was higher when grown alone or intercropped with garlic and was significantly reduced when intercropped with turnip or cauliflower. Harvest indices for garlic, turnip and cauliflower were statistically similar when grown as sole crops or intercropped with pea. The partial LER, K, A and CR for pea were higher in pea–garlic intercropping. However, partial LER, K, A and CR for intercrop were significantly higher for cauliflower and turnip in pea–cauliflower and pea–turnip intercropping systems respectively. The product of relative K values was greater for pea–garlic intercropping system, indicating a definite yield advantage. A similar trend to LER was followed by AYL. These results indicate that pea was more competitive than garlic, and cauliflower and turnip were more competitive than pea for exploiting the available growth resources. The highest MAI value was recorded for pea–garlic intercropping, reflecting that this intercropping system was more advantageous compared with other intercropping systems, indicating definite yield and economic advantages. However, pea–cauliflower intercropping system resulted in higher net income and benefit cost ratio.

Monitoring of Growth, Yield, Biomass and Heavy Metals Accumulation in Spinach Grown under Different Irrigation Sources

Growing of vegetables by the use of sewage water in peri-urban areas is a common practice which leads to heavy contamination of vegetables with metal ions. An experiment was conducted to compare the effect of canal, tube well and sewage water on growth, yield, biomass production and heavy metals accumulation in spinach. The heavy metals (Pb, Ni, Cu, Cd, Fe and Cr) contents in different water sources, soils and spinach plant parts grown with these irrigation sources were examined using atomic absorption spectrophotometer. The results declared that sewage water resulted in significantly greater growth, yield, biomass production and heavy metals contents compared with canal and tube well water and these metals contents were exceeding above the critical limits. Cu, Cd and Fe contents in sewage water irrigated soils were found above the maximum permissible limits, while Pb, Ni and Cr contents were within safer limits. Significantly greater heavy metals accumulation was recorded in edible parts of spinach grown with sewage water compared with canal and tube well water, which were exceeding the maximum permissible limits (MPLs). Canal water irrigated leaves samples also contained Cd and Fe above the permissible limits while all other metals contents were found within safe limits. The study concludes that regular examine of metals contents may possibly helpful in minimizing accumulation of these metals in the foods.