Judul: Respon Pengisian Gabah pada Padi yang Mengalami Cekaman Suhu Tinggi
Abstrak: Global warming could imply negative impact on reducing productivity of rice. The aim of this research was to study grain filling response of rice using some rice varieties grown under high temperature stress. The research was conducted at the University Farm IPB, Babakan Sawah Baru, Dramaga, Bogor. Research was perfomed using split plot design with two factors: temperature (main plots) and varieties of IR64, Ciherang, Jatiluhur, and Way Apo Buru (subplot). The results showed that the increasing of average maximum temperature of 4.07°C form 35.44°C to 39.51°C gave the same response of grain filling on each variety. Moreover it was significantly different on the maximum height, full grain at primary tip, and the weight of 1 000 grains at secondary base. High temperature has tendency on the weight of full grain at secondary tip total full grain at primary tip.
Keyword: global warming, grain filling dispersion, grain weight

Judul: Keragaan Pertumbuhan dan Produksi Beberapa Varietas Padi pada Dua Kondisi Suhu yang Berbeda
Abstrak: The objective of the research was to get the information about rice growth performance and production rice at two different temperature conditions and to study the effects of high temperature stress on production of rice. An experiment was conducted at Experimental Field Cikabayan, University Farm, IPB, Bogor. Rice was planted at two conditions, at the optimum temperature (in the open ground) and at the high temperature (in the green house). The experiment was arranged in a randomized completely block design with three replications. The extremely high tempetature will increase sterility in grain. The results showed that there were significant differences among the varieties evaluated for all traits observed. The results also showed that time of heading, time of flowering and length of penicle were not affected by temperature conditions. The traits of number of productive tiller, time of heading, time of flowering, height at generative stage, the leaf greenness at generative stage, time of harvesting, number of filled grain, number of total grain, weight of filled grain, and weight of 1000 grain were affected by genotypes x temperature conditions. Based on this study, the varieties that could maintain their yield under high temperature conditions are Situ Patenggang, Mekongga, IR-64, Kalimutu, and IPB 6R. The varieties could be used as genetic material in breeding program.
Keyword: tropical conditions, rice, high temperature

Judul: Invers Drazin dari Matriks Toeplitz Singular
Abstrak: Matriks Toeplitz adalah matriks yang setiap unsur pada diagonal utama bernilai sama dan setiap unsur pada subdiagonal yang bersesuaian dengan diagonal utama juga bernilai sama. Matriks singular adalah matriks yang tidak bisa ditentukan inversnya. Akan tetapi, dapat diupayakan untuk ditentukan inversnya menggunakan invers matriks yang diperumum. Invers Drazin merupakan salah satu jenis invers matriks yang diperumum. Pada karya ilmiah ini ditentukan invers Drazin dari matriks Toeplitz singular dengan menggunakan metode Leverrier Faddeev. Kemudian, ditentukan invers Drazin dari matriks Toeplitz singular yang direpresentasikan sebagai penjumlahan segitiga bawah dan segitiga atas matriks Toeplitz berdasar pada teorema Gohberg dan Semencul., Toeplitz matrix is a matrix in with element on the main diagonal has the same value and on the subdiagonal corresponding to the main diagonal also has the same value. Singular matrix is a matrix that has no inverse. However, it can be attempted to determine the inverse using a generalized inverse matrix. Inverse Drazin is a type of generalized matrix inverse. This paper discussed the inverse Drazin for a singular Toeplitz matrix using the Leverrier Faddeev method. Then, the Drazin inverse of the singular Toeplitz matrix which is represented as a sum of products of lower and upper triangular Toeplitz matrix based on Gohberg and Semencul theorem.
Keyword: inverse Drazine, singular Toeplitz matrix