Selekcija na uniformnost i stabilnost prinosa kukuruza

Historically speaking, both the introduction of double-cross hybrids and use of single crosses have caused the increase in grain yield and significantly improved agricultural practice. Nowadays, the uniformity of crops is regarded as an advantage of modern agriculture, since the uniformity of products is crucial in global market. Thus, uniformity of crop maturation provides both planning and efficient mechanized harvest. F1 single-cross hybrids of maize, which is an allogamous species, not only exploit heterosis, but also impose homogeneity. Basically, the uniformity of hybrids has been regarded as their crucial advantage. There are two aspects of hybrid maize uniformity: (i) genetic homogeneity and (ii) genetic stability. Genetic homogeneity refers to presence of identical genotypes, whereas genetic stability refers to phenotypic uniformity (homeostasis) in different environments. At present, yield performance of inbreds has not advanced as rapidly as performance of hybrids, especially in stressful environments. Focusing on inbred productivity combined with stability may be more appropriate strategy in the future. Poor farmers are not able to employ superior genotypes because they require considerable financial investment and farmers survive not due to high yield in good seasons, but due to enduring extreme ones. Breeding process may create genotypes in favorable seasons when genetic variance is maximal and environmental influence is minimal, which should be followed by breeding for different environments. The aim of such breeding are, most probably, genotypes intended for a specific set of conditions which, in fact, represents a convergence of two strategies of plant breeding. One should probably bear in mind the strategy of both yield improvement and survival of farmers in extreme conditions without decreasing yield of best genotypes, especially those adapted only to favorable conditions. Solution to this problem should be: financial (best possible loans), social (education), and technological (breeding improved genotypes and advanced agricultural production).Uniformnost useva se smatra poželjnom osobinom u modernoj poljoprivredi, jer je proizvod uniformnosti esencijalan na tržištu. Uniformnost u sazrevanju omogućuje planiranje biljne proizvodnje i efikasnu mehaničku žetvu i berbu. Osim toga, uniformnost useva je bitna za maksimalni prinos. Obzirom da je uniformnost malo praćena i analizirana postavili smo to za cilj u ovom radu. Uniformnost useva posebno postaje značajna osobina sa porastom i povećanjem značaja svetskog tržišta roba. Ona je redovno udružena sa smanjenjem diverziteta. Međutim, genetički diverzitet se može povećati gajenjem brojnih različitih homogenih sorata ili autohtonih populacija. Diverzitet useva se smatra poželjnim i bitnim u nekim klimatskim uslovima. Divergentne populacije koje su ranije zauzimale proizvodne kapacitete ublažavale su pad proizvodnje pod uticajem različitih stresnih uslova i na taj način smanjivale rizik. Gajenje uniformnih hibrida može rezultirati problemima u polinaciji kod kukuruza usled temperaturnog stresa koji je karakterističan u našem području. Diverzitet može biti povećan korišćenjem prirodnih populacija i gajenjem F1 hibrida sa različitom dužinom vegetacije kod kukuruza. Iz svega napred navedenog može se zaključiti da hibridi nisu najbolji za opstanak siromašnih farmera zbog značaja finansijskih ulaganja u seme i tehnologiju i opravdane zabrinutosti za nastali rizik usled gajenja neadaptiranih hibrida i smanjenja varijabilnosti kukuruza usled oplemenjivanja. Siromašni farmeri u ekstremnim uslovima održavaju genetički diverzitet kod različitih kultura i heterogenost sorata maksimalno adaptiranih datim uslovima u prostoru i vremenu. Preživljavanje u nepovoljnim godinama, ne prinos u povoljnim godinama je ključ opstanka siromašnih farmera. Ovo je verovatno važno za razvoj strategije u selekciji u cilju inkorporiranje gena za individualno ublažavanje posledica stresa inbred linija i hibrida. Za selekciju je bitno održavanje kontinuiranosti u potomstvu nosioca stabilnosti. Potomstvo može nastati selekcijom u povoljnim uslovima gde je genetička diferenciranost maksimalna, a uticaj spoljne sredine minimalan i oplemenjivanjem za različite uslove gajenja. Najverovatnije da je cilj selekcije stvaranje genotipova za date uslove spoljne sredine, što je u stvari približavanje napred navedena dva pristupa u selekciji. Ispitivanje i testiranje dobijenih genotipova mora imati ciljne uslove gajenja, lokacije. Možda pri razvoju strategije treba imati na umu strategiju povećanja prinosa i opstanka farmera u ekstremnim uslovima, pri čemu ne dolazi do smanjenja prinosa kod najboljih genotipova, naročito adaptiranih samo na povoljne uslove koji bi se sastojali u poboljšanju uslova i kulture proizvodnje istovremeno. Potencijalna solusija za ove probleme mora biti ekonomska (najbolje moguće kreditiranje) i socijalna (edukacija), kao i tehničko-tehnološka (poboljšanje genotipova i tehnologije gajenja)

Reselekcija roditeljskih komponenti elitnog hibrida kukuruza za prinos

Evaluation of donor lines as sources of new favorable alleles for the yield of grain not present in the elite hybrid parent line was conducted, or the unfavorable alleles according to Dudley method were already fixed (1987a, b). All four inbred lines, potential donors had significant values of parameter uG, so they can be used as the sources of new genes in the improvement of elite hybrid A654 x Fu4 yield. Line ZPLB36S had the greatest number of favorable predominant alleles for grain yield improvement, and the improvement should be conducted by means of self-fertilization of hybrids of this line with parental line Fu4, since the parentage of all donor lines is greater with Fu4 then with A654.Izvršena je procena linija donora kao izvora za nove poželjne alele za prinos zrna koji se ne nalaze kod linija roditelja elitnog hîbrida ili su već fiksirani nepoželjni aleli po metodi Dudley (1987a,b). Sve četiri inbred linije, potencijalni donori, su imale značajne vrednosti parametra G, tako da se mogu koristiti kao izvor novih gena u popravci prinosa elitnog hibrida A654 x Fu4. Najveći broj poželjnih dominantnih alela za popravku prinosa zrna imala je linija ZPLB36S, a popravku treba vršiti putem samooplodnje hibrida ove linije saroditeljskom linijom Fu4, jer je srodnost svih linija donora veća sa Fu4 nego sa A654

Reselekcija roditeljskih komponenti elitnog hibrida kukuruza za prinos

Evaluation of donor lines as sources of new favorable alleles for the yield of grain not present in the elite hybrid parent line was conducted, or the unfavorable alleles according to Dudley method were already fixed (1987a, b). All four inbred lines, potential donors had significant values of parameter uG, so they can be used as the sources of new genes in the improvement of elite hybrid A654 x Fu4 yield. Line ZPLB36S had the greatest number of favorable predominant alleles for grain yield improvement, and the improvement should be conducted by means of self-fertilization of hybrids of this line with parental line Fu4, since the parentage of all donor lines is greater with Fu4 then with A654.Izvršena je procena linija donora kao izvora za nove poželjne alele za prinos zrna koji se ne nalaze kod linija roditelja elitnog hîbrida ili su već fiksirani nepoželjni aleli po metodi Dudley (1987a,b). Sve četiri inbred linije, potencijalni donori, su imale značajne vrednosti parametra G, tako da se mogu koristiti kao izvor novih gena u popravci prinosa elitnog hibrida A654 x Fu4. Najveći broj poželjnih dominantnih alela za popravku prinosa zrna imala je linija ZPLB36S, a popravku treba vršiti putem samooplodnje hibrida ove linije saroditeljskom linijom Fu4, jer je srodnost svih linija donora veća sa Fu4 nego sa A654

Metode rekurentne selekcije i eksploatacija heterozisa kukuruza

Recurrent selection methods were designed to improve the agronomic value of populations by gradually increasing the frequency of favorable alleles, while maintaining genetic variability. To realize these objectives, progenies are developed, evaluated, selected and recombined in a repetitive manner. Populations improved by recurrent selection are excepted to be agronomically superior to unimproved versions and have enough genetic variability for the traits under selection to allow these populations be used for medium or long-term selection. The performance of hybrids is associated with the level of heterosis, i.e., to the superiority of hybrids over their inbred parents. To exploit heterosis efficiently, populations are grouped into heterotic groups, where population crosses within and among groups produce low and high levels of heterosis, respectively. Hybrids are then produced by crossing inbred lines from different heterotic group. Recurrent selection programs should be integrated with hybrid breeding programs so that improved populations can be used as sources of inbred lines not related to that ones developed from recycled lines via pedigree breeding. The objectives of this paper are to present the effects of recurrent selection on hybrid breeding programs; to present the changes in heterosis following recurrent selection; and to compare intra- and inter population recurrent selection. Testcross half-sib recurrent selection (TCHSRS) is for hybrid breeding programs, improvement of population crosses as well as the populations per se should be as efficient as possible, because their rates of improvement are approximately the same as for as the derived hybrids and inbred lines per se, respectively. The use of TCHSRS rather then RRS or HSRS would be the suitable strategy to accomplish the requirements of hybrid breeding programs. .Metode rekurentne selekcije imaju za cilj poboljšanje agronomskih vrednosti populacija uz postepeno povećanje frekvencije poželjnih alela osobina i održavanje genetičke varijabilnosti. U procesu selekcije neophodna je dovoljna genetička varijabilnost koja će omogućiti ovim populacijama da budu iskorišćene u procesu dugotrajnog oplemenjivanja. Stvaranje hibrida je u direktnoj vezi sa visokim heterozisom. Nivo heterozisa izmešu dve populacije je uslovljen njihovom genetičkom konstitucijom i divergentnošću. Inbred linije koje daju visok heterozis u hibridnim kombinacijama suporeklom iz različitih populacija, genetički udaljenih, koje čine heterotične parove. Cilj ovog rada je: (I) da pokaže efekte rekurentne selekcije pri stvaranju hibrida, (II) da pokaže promene u heterozisu pri različitim metodama rekurentne selekcije, (III) da uporedi razlike pri inter i intra populacijskoj rekurentnoj selekciji i (IV) da na osnovu ovih rezultata predloži novi modifikovani metod rekurentne selekcije. Obzirom na različitu efikasnost recipročne rekurentne selekcije (RRS) i half-sib rekurentne selekcije (HSRS) u inter i intra populacijskoj rekurentnoj selekciji, neophodno je primenjivati novi modifikovani metod rekurentne selekcije (test-cross half-sib rekurentnu selekciju, tj. TCHSRS). Ovaj metod selekcije u manjem procentu povećava heterozis nego RRS, ali poboljšanje međupopulacijskih hibrida i populacija per seje veće nego posle primene RRS i HSRS. TCHSRS metod se sastoji u tome da se jedna (prva) populacija koristi kao tester za drugu populaciju, te se poboljšava putem inter-populacijske rekurentne selekcije, dok se druga populacija poboljšava primenom intra-populacijske selekcije. Iz tih razloga ovaj modifikovani metod može biti nova strategija za postizanje savremenih zahteva u oplemenjivanju.

Izbor osobina za ocenu genetičke divergentnosti genotipova paradajza (lycopersicum esculentum mill)

On the basis of the seven tomato yield components (fruit length and width pericarp thickness, number of locules per fruit, number of fruits per plant fruit mass and frits mass per plant), six tomato genotypes were grouped into two clusters by applying the method of hierarchical cluster analysis. The values of the specific combining abilities (SCA) and heterosis effects in 15 tomato hybrids of F1 generation obtained by diallel crossing of six parental genotypes testified that the dendrogram of phenotypic differences was obtained on the basis of these features. It was concluded that the good hybrids with high SCA values and high heterosis effects were obtained by crossing the divergent genotypes of different clusters and high yielding genotypes of the same cluster. It was in conformity with the fact that the favourable gene recombining abilities and high heterosis effects were obtained by crossing the divergent parents and parents with the high accumulation of favourable genes for yield and yield components. Since this method was successfully applied and tested on six genotypes, it could also be applied for the characterisation and classification of the entire tomato germplasm collection. In such a way, the process of tomato selection would be greatly facilitated.Metodom hijerarhijske klaster analize izvršeno je grupisanje šest roditeljskih genotipova paradajza u dva klastera. Određivanje fenotipskih distanci vršeno je na osnovu sedam komponenti prinosa (dužine i širine ploda, debljine perikarpa ploda, broja komora ploda, broja plodova po biljci, mase ploda i mase plodova po biljci). Vrednosti posebnih kombinacionih sposobnosti (PKS) i heterozisa F1 hibrida dobijenih dijalelnim ukrštanjem između ispitivanih šest roditeljskih genotipova su poslužile za proveru pouzdanosti dobijenih fenotipskih distanci među ispitivanim genotipovima. Utvrđeno je da su dobri hibridi sa visokim PKS i visokim efektima heteroziza nastali ukrštanjem genotipova iz istih ili različitih klastera. To je u skladu sa činjenicama da se visok prinos može ostvariti ukrštanjem divergentnih genotipova. Kombinacione sposobnosti i heterozis bi trebalo proveravati za svaki konkretni slučaj kod paradajza. Pošto je metod uspešno primenjen i proveren na šest genotipova, može se primeniti i za karakterizaciju i klasifikaciju celokupne kolekcije germplazme paradajza za što veći broj osobina, čime se olakšava selekcija ove biljne vrste

Multicriterial analyses and selection of the best option for revitalization and development of the southern part of Croatian 400 kV network and connection to the power system of Bosnia and Herzegovina

The southern wing of the Croatian transmission network was constructed for 220 kV in the early 1960’s, with additional 400 kV reinforcement at the end of 1970’s. Its route of more than 200 km is quite demanding due to extreme climate, environmental specifics and related costs. However, operational experience during more than 50 years has been quite positive. Nowadays, at the end of its lifetime it is again extremely important to analyze and select the best option for network revitalization and development to serve the network users for the next 50 years, but in very different conditions of technological development, more restrictive environmental requirements, electricity market conditions and large scale RES integration. Moreover, special attention should be given to the potential opportunity and need to use this revitalization also for new interconnection to the power system of Bosnia and Herzegovina (BiH). Altogether with its length of more than 380 km this is one of the largest transmission projects in South East Europe in the last few decades. This paper presents the main findings of the multicriterial and comprehensive study covering technical, economic, financial, geographical, environmental, social and legal assessment, identifying locations of new 400 kV transmission system nodes, internal and interconnection 400 kV lines routes, together with the potential upgrade/replacement of the existing 220 kV circuits. Network analyses have been prepared on more than 180 different scenarios using PSS/E software, while market analyses were completed for 21 selected scenarios using PLEXOS software. Scenarios were based on the following criteria/uncertainties related to the power systems of Croatia and BiH: 1. analyzed time-horizons (2023 and 2028) 2. demand growth (referent, low, high) 3. analyzed operation conditions (winter/summer peak/off peak load) 4. generation scenarios (high, low, new RES, CO2 prices) 5. hydrological and climate conditions (average, extreme hydrology and wind speed) 6. power balance (import, export) 7. power transits Five main options have been initially selected as topology candidates for problem resolving. Detailed methodology and criteria for the selection of optimal option (revitalization and development scenario and topology) were developed and approved by all involved stakeholders. For selected option, based on comprehensive analyses and approved methodology , for further detailed analyses ( system reliability, technical design, investment, economics /CBA/ and environmental analyses) have been prepared, including assessment of its impact on transmission tariffs of each country. Sensitivity analyses to the most uncertain variables (investment costs and CO2 prices) were also performed. The environmental and social assessment was very demanding due to the complex governance structure and three legal frameworks to be respected (two countries, along with two entities in BiH). The Project impact was evaluated with respect to: air quality, water quality, waste management, noise, biological diversity, electromagnetic field, social measures and protected areas. This paper presents above mentioned analyses, findings and recommendations, as the most comprehensive analytical approach to the transmission line development that’s ever been applied in this region

Uticaj rekombinacija na genotipsku i fenotipsku varijabilnost prinosa kukuruza egzotične populacije

The investigations included mean values, genetic variability and phenotypic variability, heritability and genetic and phenotypic coefficients variability of yield in basic maize with 25% of the exotic germplasm incorporated and also, in the population after three and five cycles of gene recombining. To investigate influence of different cycles of gene recombinations, the trial was established after Nested Design method in two replications, on two locations. On the basis of the results obtained, it was concluded that the mean values had increased more significantly to the third than from the third to the fifth cycle of free hybridization. The additional gene recombinations influenced on the nonsignificant decrease of the genetic and phenotypic variability of grain yield. Estimated values of heritability were high and significant for yield, which indicates that they are mostly determined by the additive variance. The additional cycles of gene recombinations caused the decrease of heritability and coefficient of genetic and phenotypic variability. Bigger grain yield after three and fife gene recombination cycles, relating to the basic population, indicates to the positive effect of the additional recombination cycles to the increase of gene frequency in case of desirable traits, and the frequency of the more yielding genotypes.Proučavanjem je obuhvaćena populacija kukuruza koja u sebi ima 25% egzotične germ-plazme (1601/5 x ZPL913)F2R0 i populacija nastalih posle tri (1601/5xZPL913)F2R3 odnosno pet (1601/5 x ZPL913)F2R5 godina rekombinovanja. Ogled je postavljen po metodu Nested dizajna u dva ponavljanja na dve lokacije u toku dve godine (1993. i 1994). Prosečan prinos se povećao, a genetička i fenotipska varijansa za prinos se nisu značajno smanjile pod uticajem broja ciklusa rekombinacija i dovoljno su visoke da omoguće uspešno oplemenjivanje. Ovu populaciju treba u daljem procesu selekcije podvrgnuti delovanju metoda rekurentne selekcije

Mikroorganizmi kao indikatori plodnosti i zdravlja zemljišta pod povrćem

Microorganisms are an important element in the system soil - plant. They are indicators of fertility and/or degradation processes taking place in the soil. Dominance of beneficial groups of microorganisms controls the processes of synthesis and decomposition and determines soil quality for production of safe food. Reduced diversity of microorganisms in an indication of soil degradation and its low usefulness as habitat for fauna, microbes and plants. Microbiological analyses of soil under peas, string beans, tomato, pepper and cabbage in different locations (Bečej, Đala, Futog) have shown the number and biodiversity of microorganisms may be used to assess soil applicability for production of safe food. Biological activity of the soil was assessed on the basis of the following parameters: total number of microorganisms, numbers of diazotrophs (Azotobacter and free N-fixing bacteria), ammonifiers actinomycetes, fungi and the activity of dehydrogenase enzymes. Dehydrogenases (oxidoreductases) are fundamental in the enzymatic systems of all microorganisms. Dehydrogenase activity is an indicator of microbiological redox system in the soil and they may serve as a measure of microbial oxidative activity. The microbiological properties of the analysed soils (average results) showed their high biological value. The parameters of soil biological activity (Rumenka) displayed high values (particularly in the layer 0-50cm), which shows that the tested soils are fertile. Presence of coliform bacteria is an indicator of soil sanitary quality or a general indicator of sanitary conditions in the environment.Na osnovu zastupljenosti pojedinih grupa mikroorganizama, enzimatske aktivnosti i biodiverziteta kao pokazatelja biogenosti, može se proceniti plodnost i kvalitet/zdravstveno stanje zemljišta. Dominantnost pojedinih grupa mikrorganizama usmerava procese sinteze, razgradnje i određuje kvalitet zemljišta za proizvodnju zdravstveno ispravne hrane. Termin zdravo zemljište je ekološka oznaka sa kojom se naglašava i kvalitet, a ne samo količina prinosa u proizvodnji ratarskih i povrtarskih biljaka. Na osnovu obavljenih ispitivanja ustanovljeno je da analizirani uzorci zemljišta pod povrćem na različitim lokalitetima imaju visoku biološku aktivnost, što ukazuje na njihovu veliku plodnost. Međutim, na lokalitetu Rumenka, iako je baštensko zemljište veoma plodno postoji i visoka kontaminacija koliformnim bakterijama, što ukazuje na veoma značajan sanitarni problem po humanu populaciju. Sve ovo ukazuje na značaj ispitivanja ne samo plodnosti zemljišta već i njegovog zdravstvenog stanja kao i sanitarne ispravnosti

Promena hemijskog sastava korena kao rani indikator rizomanije šećerne repe

The aim of investigation was monitoring of change of chemical composition of sugar beet root juice in dependence of presence, that is the absence of rhizomania, as well as the intensity of the occurrence this disease in tolerant and susceptible sugar beet hybrids because of establishing of early indicators of this disease occurrence in fields of Agriculture Corporation 'Belgrade'. Considering to the specificity of production area of PKB and to the different claims about some changes of root components in plants with rhizomania, and what is connected as well as with the soil and climatic conditions in which the investigations were done, it is necessary a permanent monitoring of chemical composition of root juice because of the confirmation and monitoring of the spread of this severe sugar beet disease. On the basis of chemical analysis of sugar beet root we can conclude that increased content of sodium followed by the decrease of sugar content in sugar beet root can serve as an early indicator of occurrence of this disease. Only sodium content increase, that is decrease of sugar content in sugar beet root are not reliable indicators the occurrence or the intensity of rhizomania onset regarding the great influence of sugar beet genotype and agro-ecologic conditions in which beet is growing. .Cilj istraživanja bio je praćenje izmena hemijskog sastava soka korena šećerne repe u zavisnosti od prisustva odnosno odsustva rizomanije, kao i intenziteta pojave ove bolesti kod tolerantnih i osetljivih hibrida šećerne repe radi utvrđivanja ranih pokazatelja pojave ove bolesti na poljima Poljoprivredne korporacije 'Beograd'. S obzirom na specifičnost proizvodnog područja PKB i ne podudaranja tvrdnji o pojedinim promenama sastojaka korena kod obolelih biljaka od rizomanije, a što je povezano kako sa ispitivanim genotipovima šećerne repe i patogena, tako i sa zemljišnim i klimatskim uslovima u kojima su ispitivanja izvršena, neophodno je stalno praćenje hemijskog sastava soka korena radi potvrđivanja i praćenja širenja ove opake bolesti šećerne repe. Na osnovu hemijskih analiza soka korena šećerne repe možemo zaključiti da povećan sadržaj natrijuma praćen smanjenjem sadržaja šećera u korenu šećerne repe može poslužiti kao rani indikator pojave ove bolesti. Samo povećanje sadržaja natrijuma, odnosno smanjenje sadržaja šećera u korenu šećerne repe nisu sigurni pokazatelji pojave ili intenziteta napada rizomanije s obzirom na veliki uticaj genotipa šećerne repe i agroekoloških prilika u kojima repa raste

Tehnologija proizvodnje semena žutog zvezdana

This study is summing up basic technological operations significant for successful Birdsfoot Trefoil seed production. It gives summary of: optimal swaths per each production year, meteorological condition influences during production period; optimal sowing and seed density; and recommendation for optimal seed crop fertilization. The study outlines the issues of pollination and crop protection. It gives summary of seed crop harvesting method.U radu je dat pregled osnovnih tehnoloških operacija važnih za uspešnu proizvodnju semena žutog zvezdana. Dat je pregled izbora najoptimalnijeg otkosa u pojedinim godinama proizvodnje, značaj meteoroloških uslova u toku proizvodnje, optimalan način i gustina setve, optimalne preporuke za đubrenje semenskog useva. U radu je iznešena problematika oprašivanja cvetova, zaštita useva od štetočina i bolesti. Prikazan je način žetve semenskog useva