Wheat is an important cereal crop, which is adversely affected by water deficit stress. The effect of induced stress can be reduced by the application of salicylic acid (SA). With the objective to combat drought stress in wheat, an experiment was conducted in greenhouse under hydroponic conditions. The treatments consisted of (a) no drought (DD0 = 0 MPa), mild drought (DD1 = -0.40 MPa) and severe drought (DD2 = -0.60 MPa) by applying PEG-8000, (b) two contrasting wheat varieties Barani-17 (drought tolerant) and Anaj-17 (drought-sensitive), and (c) foliar treatments of salicylic acid (0, 50 mM, 75 mM, and 100 mM). Evaluation of wheat plants regarding biochemical, physiological, and morphological attributes were rendered after harvesting of plants. Statistically, maximum shoot and root fresh and dry weights (18.77, 11.15 and 1.99, 1.81 g, respectively) were recorded in cultivar Barani-17 under no drought condition with the application of SA (100 mM). While, minimum shoot and root fresh and dry weights (6.65, 3.14 and 0.73, 0.61 g, respectively) were recorded in cultivar Anaj-2017 under mild drought stress without SA application. The maximum shoot length (68.0 cm) was observed in cultivar Barani-2017 under no drought condition with the application of SA (100 mM). While, maximum root length (59.67 cm) was recorded in cultivar Anaj-17 under moderate drought stress without application of SA. Further, minimum shoot length (28.67 cm) was recorded in Anaj-17 under moderate drought stress without SA application. Minimum root length (38.67 cm) was recorded in cultivar Barani-17 under no drought condition without SA application. Furthermore, maximum physio-biochemical traits, including membrane stability index (MSI), chlorophyl content, photosynthetic rates, stomatal conductance, antioxidant enzymatic activities and relative water content (RWC) were found highest in cultivar Barani-17 under no drought stress and SA application at 100 mM. However, minimum values of these traits were recorded in cultivar Anaj-17 under severe drought stress without SA application. Our results also demonstrated that under severe drought, application of SA at 100 mM significantly increased leaf nitrogen (N), phosphrus (P) and potassium (K) contents and cultivar Barani-17 demonstrated significantly higher values than Anaj-17. The obtained results also indicated that the cultivation of wheat under drought stress conditions noticeably declines the morphological, physiological, and biochemical attributes of the plants. However, the exogenous application of SA had a positive impact on wheat crop for enhancing its productivity.

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PENDAHULUAN Ekosistem Teluk Bone merupakan ekosistem yang mempunyai kekhasan tersendiri. Perairannya semi tertutup dibandingkan dengan perairan selat Makassar dan laut Flores karena secara geografis terletak di sebelah Timur daratan Sulawesi Selatan dan di sebelah Barat daratan Sulawesi Tenggara. Teluk Bone telah lama dimanfaatkan untuk usaha penangkapan ikan. Usaha penangkapan ikan yang ada masih dalam skala tradisional dan dalam jumlah yang cukup banyak. Salah satu sumberdaya perikanan yang dieksploitasi di Teluk Bone adalah ikan cakalang. Potensi ikan cakalang yang ada dipengaruhi oleh pola distribusi biofisik lingkungan secara spasial dan temporal. Lingkungan biofisik yang berada dekat mulut teluk (Laut Flores) dipastikan berbeda dengan lingkungan biofisik yang jauh dari mulut teluk. Wilayah laut teluk Bone yang memiliki luas sekitar 31,837 km 2 memiliki potensi sumberdaya perikanan yang cukup besar khususnya perikanan cakalang karena 59% (13,616) ton produksi ikan cakalang Sulawesi Selatan berasal dari Kawasan Teluk Bone (Dinas Perikanan dan Kelautan Sulawesi Selatan 2006). Meskipun sumberdaya perikanan tersebut dapat pulih (renewable resources) namun tingkat kecepatan pemulihannya dapat saja tidak seimbang dengan laju pemanfaatan. Oleh karena itu pemerintah bertanggungjawab menetapkan pengelolaan sumberdaya ABSTRACTThe Bone Bay is part of Fisheries Management Zone WPPI 713 that covers Makassar strait, Flores sea and Bali sea. To such vast marine area, fisheries management can be started from smaller region, e.g. embayment waters. Biological characteristics of skipjack tuna (Katsuwonus pelamis) are some of important information for developing fisheries management in the area. This research was aimed to determine lengthweight relationship, size composititon, growth pattern and biologically feasible size of the fish. Data were obtained from fish caught by fisherman from Januari to December 2007. The bay was divided into three study areas, i.e. Northern, Centre and Southern Zones. The b coefficients for length-weight relationship in the three zones were equal 3 [not significant]. The average fork-length (FL) in each zone showed similar trends: increased from January to June, then stabilized until December. Using von Bertalanffy's growth model, the maximum FL (L ) of 759.75 mm is estimated for fish at age of 84 months. The length at first maturity of the fish is 465 mm (FL).

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