Effect of the year on the vegetative and generative phases in the growing period of maize

2005 ◽  
Vol 53 (2) ◽  
pp. 133-141 ◽  
Author(s):  
L. C. Marton ◽  
T. Szundy ◽  
I. Pók

The evaluation of an 8 × 8 diallel cross revealed that the mean length of the growing period was the same for inbred lines and their hybrids. However, the vegetative phase was 7-8% shorter and the generative phase 7-8% longer for the hybrids than for the inbred lines. The generative phase of the growing period, unlike the vegetative phase, proved to be extremely variable. Under dry conditions the length of the generative phase was negatively correlated with the length of the vegetative phase. The later a genotype flowered the less time remained for grain filling, due to the stress which curtailed the growing period. The shorter generative phase of late-flowering hybrids was the reason for the weakening of the growing period-yield correlation under dry conditions. This vulnerability of late-flowering hybrids makes selection for stress tolerance particularly important.

2016 ◽  
Vol 47 (4) ◽  
Author(s):  
Al- Khazaali & et al.

In order to identify the role of selection for early and late silking on the inbred lines from Maize (Zea Mays L.) regarding the grain yield of the consequent hybrids. Filed experiment for four seasons (spring and full 2014 and 2015) was conducted in the experimental field of Field Crop Dept., Coll. of Agric., Univ. of Baghdad. Four inbred lines (Zm19, Zm32, Zm51 and Zm61) and two testers (Zm21 late and Zm60 early silking) were used. In the first two seasons, the seeds of the four inbred lines were planted, first 10 plants that flowered early and 10 plants that flowered late were selected and the seeds of the selected plants were multiplied. The seeds of the early and late selected inbred lines were planted in the third season and crossed with testers. Crosses from the early and late flowering were produced and their seeds were cultivated in the last season. Comparison in some field and growth traits were conducted among the crosses. The experiments laid out in completely randomized block design (RCBD) at three replicates. Selection for early and late flowering parents has induced significant differences in days to flowering for all crosses and ranged between 62 days for early parents and 66 days for late parents. Also, significant differences were shown in several traits, the most prominent were crop’s and seed’s growth rate (CGR and SGR ), that correlated with seed filling duration (SFD), which contributed to increase the deposition of the dry matter into the grain for a longer period, which gave a high grain yield (GY). CGR of outstanding crosses ranged from 3.18 to 6.21 g.m-2.day, SGR ranged between 2.3 to 7.3 g. m-2.day, and the SFD between 35-38 days. In parallel, the testers (Zm21 late and Zm60 early silking) have significantly differed in their effect on the traits of some derived crosses, where the results showed significant superiority of the crosses Zm32Zm60 resulted from crossing the tester Zm60 with early silking parents selected from inbred line Zm32 on the crosses Zm32Zm21 resulted from crossing the tester Zm21 with the same parents of Zm32 in the traits of Total Dry Matter (TDM) (1.85 kg.m-2), CGR (18.28 g.m-2.day), Harvest Index (HI) (0.56), and SGR (3.3 g.m-2.day). It can be conclude  that selection for early and late silking inbred lines, as well as the effect of the early and late silking tester have a great importance in deriving hybrids of a high yield and distinct in several traits, which are all significantly contributing in increasing the GY.


HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 448E-448
Author(s):  
Mark W. Farnham ◽  
Jed W. Fahey ◽  
Katherine K. Stephenson

Broccoli (Brassica oleracea L. Italica Group) is a rich source of the aliphatic glucosinolate glucoraphanin. The glucoraphanin breakdown product, sulforaphane, has been shown to induce Phase II detoxication enzymes (e.g., Quinone Reductase) and has attracted attention as a potential chemoprotector against cancer. The objectives of this research were to evaluate the concentration of glucoraphanin in an array of diverse broccoli inbreds (doubled-haploids) largely derived from commercial germplasm and to determine if expression of glucoraphanin level in this initial evaluation is correlated with expression in a subsequent environment. In 1996, individual florets from single broccoli heads were sampled from 75 inbred lines grown in the field at Charleston, S.C., and glucoraphanin concentration was assayed. In this test, concentrations ranged from 0.04 to 2.94 μmol glucoraphanin per g fresh weight of florets and the mean concentration was 0.86. In 1997, a subset of 22 inbreds analyzed the first year were grown again in a replicated field trial. This inbred subset was made up of lines with diverse pedigrees and with high, low, or intermediate glucoraphanin concentrations. In this second year, glucoraphanin concentration had a range from 0.24 to 2.99 μmol per g fresh weight of florets and a mean of 1.37. Correlation of entry mean glucoraphanin concentration in 1997 with that in 1996 was positive (r = 0.79) and highly significant (P < 0.001) indicating that floret glucoraphanin concentration was relatively consistent between years. These observations provide evidence that floret glucoraphanin concentration has a significant genetic component.


Agronomy ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1519
Author(s):  
Samuel Henrique Kamphorst ◽  
Gabriel Moreno Bernardo Gonçalves ◽  
Antônio Teixeira do Amaral Júnior ◽  
Valter Jário de Lima ◽  
Jhean Torres Leite ◽  
...  

Getting around the damage caused by drought is a worldwide challenge, particularly in Brazil, given that economy is based on agricultural activities, including popcorn growing. The purpose of this study was to evaluate popcorn inbred lines under water stressed (WS) and well-watered (WW) conditions regarding agronomic attributes, root morphology, and leaf “greenness” index (SPAD index), besides investigating the viability of indirect selection by canonical correlations (CC) of grain yield (GY) and popping expansion (PE). Seven agronomic, six morphological root traits were evaluated and SPAD index at five different dates during grain filling. The WS (−29% less water than WW) affected significantly the GY (−55%), PE (−28%), increased the brace and crown root density, and more vertically oriented the brace and crown angles. Higher SPAD index is associated with a higher yield, and these measures were the only ones with no significant genotype × water condition interaction, which may render concomitant selection for WS and WW easier. For associating the corrections of the different traits, CC proved to have better potential than simple correlations. Thus, the evaluation of SPAD index at 29 days after the anthesis showed the best CC, and based on the previous results of SPAD index, may be used regardless of the water condition.


2011 ◽  
Vol 24 (2) ◽  
pp. 01-08
Author(s):  
B. Kumar ◽  
N. K. Patra

Opium poppy (Papaver somniferum L.) is an important medicinal plant produces more than 80 alkaloids obtained from the capsules and straw of the plant. The estimate of combining ability gives an indication of the genetic behaviour of the parental material. It is therefore, desirable to select the parents for hybridization on the basis of their per se performance and combining ability effects. The F1, F2 and their reciprocals of an eight parent diallel cross in opium poppy were studied for combining ability of seven economic traits. The mean sum of squares due to GCA, SCA and reciprocals were significant for all the traits. The magnitude of GCA variances were invariably higher than those of SCA and thus indicating the preponderance of non-additive genetic variances, which was further affirmed by the measure of average degree of dominance i.e. ?(?2s/? 2g).  Among the parents VN35I for plant height, Sanchita and VG26 for capsules per plant, VN23, VN35I and Vivek for capsule index, VG26 and Sanchita for seed and straw yield per plant, and VN35I and VG20 for morphine content were found good general combiners. Earliness being a desired trait, parent VG20 having significant negative GCA estimates coupled with per se performance can be considered as good general combiner for early flowering. Inclusion of good general combiners in a multiple crossing program or an inter-mating population involving all possible crosses among them subjected to bi-parental mating may be expected to offer maximum promise in breeding for economic traits.DOI: http://dx.doi.org/10.3329/bjpbg.v24i2.17000


2019 ◽  
pp. 1-23
Author(s):  
А.В. Семенютина ◽  
С.Е. Лазарев ◽  
К.А. Мельник

Представители родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) относятся к экономически важным и перспективным, для деградированных ландшафтов засушливого региона, видам растений. Несмотря на это до последнего времени отсутствуют сведения по многим видам этих родовых комплексов, связанные с вопросами экологических основ семеноведения и их репродуктивной способности в условиях светлокаштановых почв Волгоградской области. Все это направлено на выявление и расширение перспективных ареалов культивирования для лесомелиорации и озеленения населенных пунктов. Цель исследований изучение репродуктивной способности представителей родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) в коллекциях ФНЦ агроэкологии РАН и выявление особенностей их селекционного семеноведения для лесомелиорации и озеленения населенных пунктов в сухостепных условиях. Объектами исследований являлись виды и формы рода Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana х pseudoacacia, и Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), произрастающие в кластерных участках коллекций ФНЦ агроэкологии РАН, кадастр 34:34:000000:122, 34:34:060061:10. Разработка основ селекционного семеноведения базируется на изучении репродуктивных особенностей выделенных для целевого использования собственных биоресурсов с учетом возможностей всестороннего изучения генеративных качеств и оценки биологического потенциала. Выявлено, что стабильность плодоношения фиксируется через несколько лет после вступления в генеративную фазу: у Robinia и Gleditsia 67 лет. Первое цветение у Gleditsia triacanthos и G. texana, G. aquatica наблюдалось в возрасте 5 лет, G. japonica 6, G. caspica и G. sinensis 8 лет. Завязываемость плодов зависит не только от возраста растения, но и от погодных условий во время цветения. На семенную продуктивность влияет количество выпавших осадков и сумма активных температур в период созревания плодов. Формирование более крупных плодов и семян наблюдается в возрасте до 15 лет. В результате исследований (20172019 гг.) выявлено влияние лимитирующих факторов на биологический потенциал цветения, плодоношения и семенную продуктивность для определения ареалов их культивирования. Representatives of generic systems Robinia, Gleditsia are economically important and promising for degraded arid landscapes of the region, types of plants. Despite this, until recently, there is no information on many types of these generic complexes related to the environmental foundations of seed and their reproductive capacity in light chestnut soils of the Volgograd region. All this is aimed at identifying and expanding promising areas of cultivation for forest reclamation and greening of settlements. The aim of the research is to study the reproductive capacity of representatives of ancestral complexes Robinia, Gleditsia in the collections of the Federal scientific center for Agroecology Russian Academy of Sciences and the identifying features of their selection of seed for forest reclamation and landscaping of settlements in the dry steppe conditions. The objects of research were species and forms of the genus Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana x pseudoacacia and Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), growing in the cluster areas of collections of FSC Agroecology RAS, cadastre 34:34:000000:122, 34:34:060061:10. The development of the principles of seed breeding is based on the study of reproductive characteristics of the allocated for the targeted use of their own bioresources, taking into account the possibilities of a comprehensive study of generative qualities and assessment of biological potential. It was found that the stability of fruiting is fixed a few years after entering the generative phase: Robinia and Gleditsia 67 years. The first flowering in Gleditsia triacanthos and G. texana, G. aquatica was observed at the age of 5 years, G. japonica 6, G. caspica and G. sinensis 8 years. Fruit setability depends not only on the age of the plant, but also on weather conditions during flowering. Seed productivity is affected by the amount of precipitation and the amount of active temperatures during the ripening period. The formation of larger fruits and seeds is observed in the age of 15 years. As a result of studies (20172019), the influence of limiting factors on the biological potential of flowering, fruiting and seed production to determine the areas of their cultivation was revealed.


1966 ◽  
Vol 67 (2) ◽  
pp. 235-237 ◽  
Author(s):  
D. A. Bond ◽  
J. L. Fyfe ◽  
Gillian Toynbee-Clarke

The yields of seed from a hybrid, one of its parents and different mixtures of the hybrid and parent were compared in the case of two different hybrids. Open-pollinated controls were included in the trial, which was sown at about the normal rate for beans. With both hybrids a mixture of 11 of hybrid to 1 of parent yielded as well as the hybrid itself and mixtures of 2 of hybrid to 1 of parent yielded in both cases about 7 cwt./acro more than the mean of the open-pollinated controls. With the higher-yielding hybrid, which had less contrast in vegetative vigour between hybrid and parent, mixtures in the proportions 5:1 and 2:1 showed declining yields, but with the other hybrid they yielded as well as the pure hybrid.


1966 ◽  
Vol 46 (1) ◽  
pp. 59-67 ◽  
Author(s):  
Eric D. Putt

Heterosis occurred for the eight plant and seed characters studied. It was most frequent for yield of seed and height of plant. Mean squares for general combining ability (gca) and specific combining ability (sca) were significant (P =.01) for all characters. The estimated components for gca were greater than for sca for days to mature, weight per bushel, and percent oil in the seed; less for height and yield of seed; and essentially the same for days to bloom, diameter of head, and weight per 1000 seeds.The yield of seed and percent oil in the seed, for the highest ranking 100 synthetics that could be composed from the 10 lines, was predicted in F6 assuming 50 and 60% outcrossing between F2 and F6. Virtually all values exceeded the mean performance of four check samples of commercial hybrids. Many exceeded the highest rank check for oil content in the seed. Fourteen of the highest ranking 100 synthetics for yield and 30 for oil content consisted of two or three lines. It was concluded that synthetics can be superior to the present hybrids in heterosis and that desirable synthetics can be made from only a few lines.


1966 ◽  
Vol 19 (6) ◽  
pp. 1061 ◽  
Author(s):  
EJ Eisen ◽  
BB Bohren ◽  
HE Mckean

The diallel cross has been used frequently in plant experiments to partition the genetic variation into general and specific combining abilities of inbred lines. The statistical models developed for analysis of diallel crosses in plants have been used in a number of studies of diallel crosses in mammals and poultry, without due consideration to the presence and effect of the sex chromosomes.


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