Judul: Dinamika stomata pada padi varietas Hawara Bunar, IR64, Mutan, dan Transgenik saat cekaman kekeringan.
Abstrak: Penggunaan varietas padi yang beradaptasi baik pada kondisi cekaman kekeringan sangat penting agar produksi padi tetap stabil. Penelitian ini bertujuan menganalisis dinamika stomata, laju transpriasi, dan komponen pertukaran gas pada empat genotipe tanaman padi pada kondisi cekaman kekeringan. Penelitian ini menggunakan rancangan acak lengkap dua faktor dengan lima ulangan. Faktor pertama adalah empat genotipe padi, sedangkan faktor kedua adalah dua taraf cekaman kekeringan. Tanaman padi berumur 73 hari setelah tanam (HST) diberi cekaman kekeringan selama 10 hari. Peubah yang diamati meliputi persentase stomata membuka dan menutup pada bagian atas dan bawah daun, laju transpirasi, konduktansi stomata, dan kandungan air di rongga stomata. Hasil penelitian menunjukkan persentase stomata membuka pada bagian atas daun berbeda nyata antar genotipe dan antar perlakuan cekaman kekeringan, sedangkan pembukaan stomata pada bagian bawah daun hanya dipengaruhi oleh perlakukan cekaman kekeringan. Persentase stomata membuka pada kondisi cekaman kekeringan pada varietas Hawara Bunar, IR64, mutan, dan transgenik berturut-turut 8,7, 3,0, 11,6, dan 36,1% lebih rendah dibandingkan persentase stomata membuka pada kondisi tanpa cekaman kekeringan. Semua genotipe padi hanya mengalami cekaman kekeringan sedang, sehingga perbedaan pembukaan stomata belum mampu menyebabkan perbedaan laju transpirasi, konduktansi stomata, dan kandungan air interselular antar pelakuan cekaman kekeringan., The utilization of rice varieties that are well adapted to drought stress conditions is important to maintain rice production stability. The study aimed to analyze stomatal dynamics, transpiration rates, and gas exchange components of four rice genotypes under drought stress conditions. The study used two-factor completely randomized design with five replications. The first factor was four rice genotypes, while the second was two drought levels. Rice plants 73 days after planting (DAP) were drought-stressed for 10 days. Variables observed were percentage of stomatal opening and closing, transpiration rate, stomatal conductance, and water content in the stomatal cavity. The results showed the percentage of stomatal opening on the upper of leaves was significantly different among genotypes and between drought treatments, while stomatal opening on the underside of leaves was only affected by drought treatment. The percentage of stomatal opening under drought stress for Hawara Bunar, IR64, mutant, and transgenic were 8.7, 3.0, 11.6, and 36.1% respectively, which was lower than normal condition. The differences in stomatal opening did not cause the differences in transpiration rates, stomatal conductance, and intercellular water content between drought stress treatments, suggesting that all rice genotypes only experienced mild stress.
Keyword: genotipe padi, kekeringan, konduktansi stomata, komponen pertukaran gas, pembukaan stomata

Judul: Karakteristik Sel Buliform dan Respon Fisiologis Padi Varietas  Hawara Bunar dan Mutannya terhadap Cekaman Kekeringan
Abstrak: Cekaman kekeringan mampu mempengaruhi laju fotosintesis, tingkat kebocoran elektrolit, dan penggulungan daun padi. Hasil studi terhadap varietas Hawara Bunar, galur mutan Hawara Bunar, galur mutan Hawara Bunar silencing B11, serta varietas IR64 menunjukkan tingkat penggulungan yang sangat berbeda ketika mendapat cekaman kekeringan. Hal ini diduga terdapat perbedaan karakteristik sel buliform dari keempat genotipe padi tersebut. Penelitian ini dilakukan untuk menganalisis karakteristik sel buliform serta respon fisiologis dari padi varietas Hawara Bunar, galur mutan Hawara Bunar, galur mutan Hawara Bunar silencing B11, serta varietas IR64 terhadap cekaman kekeringan. Percobaan ini merupakan percobaan faktorial yang dirancang secara Acak Lengkap dengan 2 faktor, yaitu faktor genotipe padi dan faktor cekaman kekeringan. Kegiatan yang dilakukan pada penelitian ini meliputi penanaman dan pemeliharaan tanaman, perlakuan cekaman kekeringan, pengamatan sel buliform dan analisis fisiologis. Kuantifikasi data dilakukan dengan software ImageJ dan R studio, analisis statistik menggunakan Two-Way Anova pada α 0,05 dan dilanjutkan dengan uji LSD. Hasil analisis jumlah sel buliform dan karakter fisiologis menunjukkan bahwa padi galur mutan Hawara Bunar, galur mutan Hawara Bunar silencing B11, serta varietas IR64 merupakan varietas yang sensitif terhadap cekaman kekeringan, sedangkan Hawara Bunar merupakan varietas yang toleran terhadap kekeringan. Varietas Hawara Bunar mampu mempertahankan kandungan klorofil, laju fotosintesis, kadar CO2 dan H2O tetap tinggi dalam kondisi cekaman kekeringan, namun dalam kondisi yang sama memiliki kenaikan jumlah dan luas sel buliform, kebocoran elektrolit, dan suhu daun yang lebih rendah dari genotipe sensitif kekeringan., Drought stress affects photosynthesis rate, electrolyte leakage, and rice plant leaf rolling. Pevious study on rice variety Hawara Bunar variety and and its mutants showed very different rolling rates when exposed to drought stress. It is sugested that there are differences in characteristics of bulliform cells among those rice genotypes. Therefore, the study aimed to analyze the characteristics of bulliform cells and the physiological response of rice variety Hawara Bunar, Hawara Bunar mutant line, Hawara Bunar silenced B11 mutant line, and IR64 variety to drought stress. This experiment is a factorial experiment that was designed completely randomized with 2 factors, namely the rice plant genotype factor and the drought stress factor. The activities in this research include planting and maintenance, drought stress treatment, observation of bulliform cells and physiological analysis. Data quantification was performed using ImageJ and R studio software, statistical analysis using Two-Way Anova at α 0,05 and continued with LSD test. Analysis result of bulliform cells and physiological characteristics showed that rice Hawara Bunar mutant line, Hawara Bunar silenced B11 mutant line, and rice variety IR64 are sensitive to drought stress, while Hawara Bunar is a drought tolerant variety. Rice variety Hawara Bunar was able to maintain high chlorophyll content, photosynthetic rate, CO2 and H2O levels under drought stress conditions, but under the same conditions showed an increase in number and area of bulliform cells, electrolyte leakage, and lower leaf temperatures than drought sensitive genotypes.
Keyword: bulliform cell, drought, leaf rolling, physiological, tolerance

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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