Study On The Heterosis And Inheritance Characteristics Of Huang Zao 4 And Its Improved-lines

This paper studied Huang zao 4 and its improved-lines which has an important contribution to our country. First, density tolerance analysis with Huang zao 4, Chang 7-2, Zhong 106, A87 and Zhe 461 under 6.0×104 plant/hm2, 7.5×104 plant/hm2 and 9.0×104 plant /hm2; Second, Combining ability, genetic parameters and correlation analysis with 30 hybrids witch combined 5 Tangsipingtou lnbred lines with 6 other groups of inbred lines under 6.0×104 plant/hm2, 7.5×104 plant/hm2 and 9.0×104 plant /hm2. results show that:1. Advantages traits of Huang zao 4 and its improved-lines under high density. Ear length, bald length and axis diameter are Huangzaosi’s advantages secret resistance traits; individual yield, ear length, bald length, rows per ear, kernels per row, ear diameter, axis diameter and cob weight are Chang7-2’s advantages secret resistance traits; individual yield, ear length, bald length, kernels per row and ear diameter are Zhong 106’s advantages secret resistance traits; individual yield, ear length, ear height, bald length, kernels per row, ear diameter and axis diameter are A87’s advantages secret resistance traits; plant height, ear height, axis diameter and cob weight are Zhe461’s advantages secret resistance traits.2. Analysis density tolerance of Huang zao 4 and its improved-lines. Good resistance to density stability Chang 7-2, are resistant to high density inbred lines; Huang zao 4, Zhong 106, A87 under pressure density traits stability in general, moderate resistance to high density inbred lines; Zhe 461 was sensitive under high-density pressure, poor stability, are intolerant of high density inbred.3. Heterosis of Tangsipingtou groups with other groups. Huang zao 4 and its improved-lines have heterosis with Reid, Lancaster, Lvdahonggu groups inbred lines, a part of the hybrids under 9.0×104 plant /hm2 with higher yield per plant veterosis value. Tangsipingtou germplasm has the value of resistant density tolerance.4. GCA analysis of main traits about Huang zao 4 and its improved-lines. The traits of individual yield, ear length, plant height, ear height, rows per ear, kernels per ear rows and cob weight were the positive GCA value under 3 densities, the bald length trait was negative GCA value of Huang zao 4; plant height, ear height, bald length, rows per ear and ear diameter were the positive GCA value under 3 densities, individual yield, ear length, axis diameter and cob weight were negative GCA value of Chang 7-2; individual yield, ear length, plant height, ear height, kernels per ear rows, axis diameter and cob weight were the positive GCA value under 3 densities, rows per ear trait was negative GCA value of Zhong 106; individual yield, ear length, bald length and ear diameter were the positive GCA value under 3 densities, plant height, ear height and cob weight were negative GCA value of A87; individual yield, ear length, plant height, ear height, bald length, kernels per ear rows, ear diameter and cob weight were negative GCA value of Zhe 461.5. SCA analysis of individual yield. There are 9 hybrids with positive SCA value as PH6WC×Huang zao 4, J1255×Huang zao 4, and so on, have the potential of resistant density tolerance.6. Analysis of genetic parameters. At 6.0×104 plant/ hm2 the narrow heritability value of individual yield and axle traits are highest; At 7.5×104 plant/ hm2 the narrow heritability value of ear rows, ear length, plant height, kernels per row and ear diametertraits are highest; At 9.0×104 plant/ hm2 the narrow heritability value of bald length, ear height and axis diameter traits are highest. Description 7.5×104 plant/hm2 density is the best breeding for expanded Tangsipingtou germplasm. At 7.5×104 plant/ hm2 the narrow heritability value of individual yield and bald length traits are lowest, not in the early generation selection.7. Regression analysis. Under low-middle density, choice plant type and ear traits is the premise of improving individual yield, under high density, choice ear traits is the premise of improving individual yield. Therefore, choice the ear characteristics is the key to improved individual yield.