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To determine the genetic-physiologic and genetic-morphologic components in soybean, live genotypes were grown in a randomized complete block design of four replicates. Data were recorded on plants grown in a one square meter of each experimental unit. The genetic-physiologic components of the five genotypes of soybeans ranged between 3.8 and 8.1 g/m/d of growth rate, 95 and 137 d of growing season, 360 and 1110 g/m2 TDM, and 28.1% and 40.4% of harvest index. Meanwhile, the genetic -morphologic components ranged between 765 and 1310 pod/m , 1.4 and 2.1 seed/pod, and 95 and 177 mg/seed which gave 145 and 393 g/plant of seeds. Results obtained showed that plant growth rate was the most effective variable to obtain high TDM/plant, then days of growing season. The best cultivar to give higher TDM and seed yield should has longer period from planting to blooming, along with higher growth rate and moderate harvest index. However, the most important genetic-morphologic component was number of pods/plant, then seed weight. So, to develop a high yielding cultivar of soybean we need to select plants of higher growth rate, higher number of pods/plant, longer period from planting to blooming and moderate harvest index.

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Several theories and results of many researchers worked on hybrid vigour in crop plants were reviewed and discussed .It was concluded that hybrid vigour is a quantitative complex syndrome resulting via different gene action of many gene pairs. It was also concluded that hybrid vigour is seldom to be due to one case of gene action. So, it is most likely to come out by three cases of gene actions act together at the same time:1. Codominance effects of some major favourable allelic genes (on some chromosomes) cause genes to complement each other (intra- genie interaction) to show the vigour of traits in the hybrid.2. Coepistasis and semiepistasis effects of some major favourable nonallelic genes (on same or another chromosome) cause genes to complement each other (inter- genie interaction) to show the vigour of traits in the hybrid.1.3. Partial dominance and dominance effects of many genes act to cover the negative effects of deleterious genes. Additive gene action might be involved too. Masking the effects of deleterious genes is most likely to take place in each hybrid resulting from crossing inbreds. However, this case is seldom to be as the major reason of hybrid vigour.

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Four subspecies of maize; saccharata, indentata, indurata and everta were intercrossed. This was to study the direct effect of pollens on seed characteristics (xenia). The result obtained showed that xenia was not exist in the Fl seeds of those crosses for pollens had no direct effect on any seed trait studied. However, the female cytoplasm controlled all seed traits unless hybrid vigour or dominance appears. That was attributed to the fact that female contributes with 2 nuclei and the pollen with one nucleus through fertilization. A maximum of 51.6% hybrid vigour in seed weight was found in saccharata when used as female, while a negative heterosis (- 25.6%) was found in seed weight when everta used as female?The inheritance of colour and shape of Fl seeds was controlled by the female cytoplasm, but in some crosses it gave a midparent value. Meanwhile, dent shape was similar in inheritance to that of colour and shape of seed. The saccharata subspecies gave always a dented seed when used as female in regardless of pollen, while the other three subspecies (when used as female) and crossed by saccharata gave either flint trait or midparent. It was concluded from this work that traits of Fl seeds are under female cytoplasm control unless heterosis or dominance appears. That is to say, hybrid vigour could appear immediately (if exist) on the Fl seeds of the crossed female and not the xenia effect.

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To determine the impact of 3 cycles of selfing and selection on inbreds of maize in field performance and molecular variation, seeds of 6 A- lines, 6 maintainers (B- lines) and 6 restorers (R- lines) were planted. That was on the farm of Field Crop Sci., Coll. of Agric., Univ. of Baghdad across 6 planting seasons during 2008-2010. Previous published results of this article showed that performance of selected inbreds was different as compared to original populations. Then, samples were taken from these inbreds and analyzed for their DNA. Ten RAPD primers were used and gave 139 DNA bands of molecular weight ranged between 264-2717 bp. Coefficient of Nei and Li of genetic similarity (GS) revealed that similarity ranged between 76% to 97% between original and selected populations. The highest GS (97%) was between inbreds R6-o and R6-s, while the lowest GS (76%) was between inbreds R2-o and R2-s. However, genetic similarity among all inbreds ranged between 57% to 89%. Meanwhile inbreds of higher genetic diversity did not give higher performance or higher hybrid vigor. This implies that hybrid vigor is not necessarily correlated with genetic diversity, or such tests need more primers, or hybrid vigor is correlated with a specific favorable number of diversed QTL integrate so well when their inbreds crossed.

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Water deficit stress is one of the most prominent factors that limits yield of many crops in the world. This will hold true under rain fed and irrigated agriculture. This research targeted identification of the plant traits that are more related to water deficit tolerance. Three non-oil sunflower (Helianthus annuus L.) cultivars were compared; shumoos , select 1, and select 2. Seed of the cultivars were planted on the farm of Field Crops Station of the College of Agric., University of Baghdad in 2013.Three irrigation levels of water were used ; 320, 400, and 560 mm/season. A randomized complete block design of four replications in a factorial arrangement was used. When cultivars compared, select 2 gave higher number of seeds (1366/capitulum), 21.2 cm capitulum diameter, 99.7 days to physiological maturity, higher seed yield (144g/plant) and high seed weight (119.2mg/seed). Crop growth rate of cultivar was increased with increased level of irrigation water. At 320 mm, crop growth rate was 5.5 g/plant/day, increased to 7.1 g/plant/day at 560 mm/season. Seed filling period and plant height had higher ratio of genetic to environmental variance than other traits. Chlorophyll index, percent water loss (PWL) and days to 90% flowering had higher ratio of genetic to environmental variance than the rest of other studied traits. These five traits had at least 76% h2b.s, and they were similar in P.C.V% and G.C.V%, so, they were recommended to be used as parameters to select sunflower genotypes tolerant to water deficit stress studies in a specific geographic area. Meanwhile, genotypic resultant values were coincided with many traits detected for drought stress tolerance by genetic to environment variance ratio.

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Via mitochondrial genes, eukaryotes: such as plants, animals, human and yeast have evolved ways of cellular suicide that are known as Programmed Cell Death (PCD). In multicellular organisms, the organized destruction of cells is important in development and immunity and for forming body and specific organ shapes, as well as for removing superfluous, unwanted, damaged or infected cells. Furthermore, disfunction of PCD could lead to various diseases in humans, including cancer and several degenerative diseases. Two characterized systems for the study of plant PCD are those of the Hypersensitive Response (HR), which is often observed during plant–microbe interactions, and the development of tracheary elements in the xylem of vascular plants. A simplified depiction of the sequence of cytological events that take place during these forms of plant PCD is contrasted with those of "apoptosis", the well studied form of animal PCD. The "clean" process of apoptosis effectively contains the contents of the dead cell for removal by other cells and avoids activating an inflammatory response in animals. In the case of HR-associated cell death and the terminal differentiation of tracheary elements, the contents of the dying cells are not engulfed by other cells. In addition, the "corpse" of the dead cell is held in place by the cell wall, and for mature tracheary elements, the cell wall is reinforced during the early phase of PCD and carries out the essential function of mechanical support and transport after autolysis. The final collapse of the vacuole immediately precedes nuclear DNA fragmentation, which occurs at late stages of the cell death process before the final autolysis of the cell. These "key" characteristics therefore distinguish plant PCD from that of classic apoptosis and indicate that specialized features and pathways have probably evolved to control and execute the death program in plant cells. Taxonomy of all forms of PCD based on inhibitors, activators, and identified biochemical pathways involved in each form of PCD, and that should offer new insight into cell death associated with various disease states, and ultimately introduce new therapeutic approaches in human and animals. In plants, and by controlling PCD mechanism, the system capacity constant could be increased, and ultimately, the economic yield.

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The experiment was carried out to test if the percent of vigorous seedlings emerged from sand in the laboratory will good fit with percent of plants grown in the field giving mean grain performance and up ( + Ẍ). The seeds used were of synthetic maize B-106. The experiment was conducted for two seasons on the farm of Field Crop Research Station/College of Agric./Univ. of Baghdad during spring and fall of 2010. Zinc metal containers with dimensions of 24.5×24.5×5 cm were prepared. Silica pure sand was used in these containers of 4 cm deep. These were watered, then a special wooden finger (100 fingers) were pressed on sand of containers to have 100 holes for planting. Seeds of R-106 maize cultivar were planted and watered. Percent of vigorous seedlings were taken after 72h and each 12h. Same seeds were planted in the farm and grain yield of twenty replicates were recorded. Data of lab and field were tested by t-test, and the prediction of performance of seed lot was fit. This imply that we can test any maize seed lot for the percent of ( + Ẍ) performance plants by percent of vigorous seedlings emerged from sand(SE/h96). However, this test could be used for other crops in the future.

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To investigate the effects of seed position on the cob (lower and upper third),seed harvested at physiological and one month later and 200 and 400 kg N/ha when grown in spring and fall of the next year, using seeds of maize synthetic B-106. The experiment was conducted for four seasons on the farm of Field Crop Research Station/College of Agric./Univ. of Baghdad during spring and fall of 2009 and 2010. Results showed that seeds produced in the spring and fertilized with 400 kg.ha-1 gave higher seeds.plant-1 (343 and 601)and grain yield.plant-1 (78 and 124 g.plant-1)as compared to 200 kg.N.ha-1 which gave lower grain.plant-1 (64 and 112)for both seasons, respectively. Late harvest of spring grown seeds gave higher plant leaf area (0.608 m2), crop growth rate (2.3 and 4.5 g.m-2.d-1) and plant dry matter (229 and 283 g.plant-1),that increased seed yield (78 and 120 g) as compared to early harvest which gave lower plant seed yield (69 and 108 g), both seasons, respectively. Accordingly, to produce maize seeds of high agricultural quality, we should take spring grown seeds fertilized with 400kg.N.ha-1 , and harvested one month after physiological maturity. However, to have high seed yield for industry or feed, we recommend fall grown seeds taken from lower third of ear, and fertilized with 400kg.N.ha-1. Lower third seeds grown in the fall gave plant growth rate (2.2 and 4.2 g.m-2.d-1), plant dry matter (205 and 374 g),ear seed number (322 and 601) and plant grain yield (73 and 128 g) as compared to lower plant yield of upper third seeds which gave (67 and 108 g.plant-1),for both seasons, respectively. Genetic contamination was higher in lower or upper third of ear when foreign pollinator pollens available, early or late, in the seasons,respectively.

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A field experiment was undertaken on the Research Station of the Dept. of Field Crop Sci. of the College of Agric. / Univ. of Baghdad . This was to study chlorophyll content (CC) and disappearance in a cross of maize and its parents, and its relationships to hybrid vigor under two levels of N (150 and 300 kg/ha) and two population densities (35 and 70 thousands plant/ha). Near 75% silking , (CC) in the ear leaf was 20.4 and 23.6 mg /g for the parents, and 21.3 and 23.8 mg/g fresh weight for hybrid under 150 and 300 kg N/ha , respectively with the density 35 thousands plant/ha. Whereas, at the higher density (70,000 ppha), the values became 17.2 and 18.8 for the parents, and 19.2 and 19.7 mg/g fresh weight for the hybrid, for the two levels of N, respectively and D2. However, at physiologic maturity, at higher density and N, (CC) values in the ear leaf became; 15.8 mg/g as average of parents, and 17.4 mg/g for the hybrid. This shows the higher level of (CC) in the hybrid and its stability at maturity .Higher nitrogen (150 to 300 kg N/ha) increased leaf area duration. The hybrid gave wider leaf area and higher chlorophyll content compared to its parents. One of the features of hybrid was the early transition from vegetative to reproductive stage compared to its parents. So, the hybrid produced 508 kernal / ear , while the inbreds gave 365 kernal /ear. Process of grain filling period and maturity depended on system capacity constant (SCC). The hybrid gave 47% HI compared to 31% for the inbreds. This led the hybrid to produce grain yield 11.98 t/ha and the inbreds 7.3 t/ha . The conclusion from results indicate that hybrid stability of (CC) in the leaf at maturity led to increased TDM and faster transition from vegetative to reproductive stage ; higher number of kernel /ear , and the higher grain yield in unit of area.

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To predict percent of vigorous plants expected to grow in the field from a seed lot of maize by percent of vigorous seedlings emerged from sand , seeds of two synthetics of maize ; B- 106 and 5018 stored for one year under poor storage were used. Zinc metal containers with dimensions of 24.5 × 24.5 × 5 cm were prepared . silica pure sand was used in these containers of 4 cm deep . At the same time , a wooden clamp of 100 fingers was made . Fingers were 5 cm long and 8 mm diameter .One hour after watering the containers the clamp was pressed on containers to have 100 holes for planting . Seeds were planted in these holes , covered with dry sand and watered . This test was replicated twenty times . Seeds of the two cultivars were also planted in the field with twenty replicates , each of 100 plants . Data was obtained after 96 h from planting on vigorous seedlings emerged in the containers , whereas , percent of vigorous plants were recorded after 6 weeks in the field . Data obtained was analyzed by t – test , then in a factorial analysis with RCBD of four replicates . Results obtained showed that percent of vigorous seedlings from the sand test ( SE /96 ) was a very good estimate to predict percent of vigorous plants in the field expected from a maize seed lot . It was recommended to use this test to predict percent of cultivar mean performance in maize or other seed crops in the future .

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