ABSTRACT The objective of this study was to assess seed health and the effect of plant extracts on Fusarium oxysporum f. sp. vasinfectum mycelial growth and sporulation, plant pathogen reduction in seeds and fusariosis control in okra seedlings. Health was assessed by the Blotter Test, after immersing the seeds in natural extracts and plating. To verify the mycelial growth of the plant pathogen, the extracts were incorporated in PDA culture medium and the pathogen was added and assessed, including the spore count. In the greenhouse, the seeds were immersed in the extracts, sown and at 15 days they were sprayed with extracts, at 21 days inoculated with the pathogen and disease severity on the seedlings was assessed 7 days later. There were higher incidences of Fusarium sp. and Rhizopus stolonifer in the seeds of the cultivars Valença and Santa Cruz 47. The extracts that resulted in lower pathogen incidence was basil, in cv. Valença and cinnamon and neem, in cv. Santa Cruz 47. The neem treatment presented the best inhibition percentage and the lowest sporulation mean in mycelial growth of the pathogen. Neem presented higher disease incidence control in the seedlings of cv. Valença and basil on the seedlings of cv. Santa Cruz 47.

Resumo O objetivo deste trabalho foi traçar o perfil fisiológico, sanitário e o controle de fitopatógenos em quatro espécies de sementes florestais. Antes dos testes, as sementes de juçara (Euterpe oleracea Mart.), jenipapo (Genipa americana L.), urucum (Bixa orellana L.) e cuia (Crescentia cujete L.) foram desinfestadas com álcool 70%, hipoclorito de sódio a 5% e água destilada. Os testes de germinação, emergência e sanidade foram realizados conforme a RAS. No manejo alternativo, foram testados o isolado de Bacillus methylotrophicus e o óleo de nim, sendo realizado por meio de dois experimentos independentes em delineamento inteiramente casualizado (DIC), com quatro tratamentos e oito repetições. O experimento “um” foi realizado através da microbiolização das sementes com B. methylotrophicus e, no experimento “dois”, as sementes foram pulverizadas com óleo de nim a 15% com auxílio de pulverizador manual. As sementes de juçara, jenipapo, urucum e cuia obtiveram 9,0; 67,00; 17,50 e 63,5% de germinação; 0,5; 7,00; 0,5 e 63;5% de emergência; 22,81; 12,15; 15,66 e 8,73% de teor de água, respectivamente. Os fungos fitopatogênicos de maior incidência foram Penicillium sp., Aspergillus sp., Fusarium sp., nas sementes florestais de cuia, jenipapo, juçara e urucum, respectivamente. As sementes tratadas com óleo de nim e as microbiolizadas com B. methylotrophicus obtiveram controle significativo para Aspergillus sp.; Penicillium sp., em sementes de jenipapo; Lasiodiplodia sp. e Fusarium sp. em sementes de urucum. Portanto, o uso de B. methylotrophicus e óleo de nim pode ser considerado alternativa viável na redução de patógenos de sementes florestais.

Abstract The objective of this work was to trace the physiological, health and phytopathogen control in four species of forest seeds. Before the tests and treatments, the juçara (Euterpe oleracea Mart.), genipap (Genipa americana L.), annatto (Bixa Orellana L.) and calabash (Crescentia cujete L.) seeds were washed three times with 70% alcohol, 5% sodium hypochlorite and distilled water. Germination, emergency and health tests were performed according to the RAS. In the alternative management, Bacillus methylotrophicus isolate and neem oil were tested, being carried out through two independent experiments in a completely randomized design (DIC), with four treatments and eight repetitions. Experiment one was carried out by microbiolizing the seeds with B. methylotrophicus and, in experiment two, the seeds were sprayed with 15% neem oil with the aid of a manual spray. The seeds of juçara, genipapo, annatto and calabash, obtained 9.0%, 67.00%, 17.50%, 63.5% of germination; 0.5%, 7.00%, 0.5%, 63.5% emergency; 22.81%, 12.15%, 15.66%, 8.73% water content respectively. The phytopathogenic fungi with the highest incidence were Penicillium sp., Aspergillus sp., Fusarium sp., in the forest seeds of calabash, genipap, juçara and annatto, respectively. The seeds treated with neem oil and those microbiolized with B. methylotrophicus obtained significant control for Aspergillus sp; Penicillium sp., In genipap seeds; Lasiodiplodia sp. and Fusarium sp. in annatto seeds. Therefore, the use of B. methylotrophicus and neem oil can be considered viable alternatives to reduce pathogens from forest seeds.

O milho está entre os cereais mais cultivados e utilizados pela população mundial. Com o objetivo de efetuar o levantamento da comunidade de plantas daninhas no cultivo de milho em monocultivo e em consórcio, com diferentes Fabaceae, cultivado sob diferentes manejos, este trabalho foi realizado durante o período da primavera/verão de 2011/2012. Avaliaram-se os tratamentos: milho em monocultivo com adubação NPK na semeadura e com capina, milho em monocultivo sem adubação NPK na semeadura e com capina, milho em monocultivo com adubação NPK na semeadura sem capina, milho + mucu-preta, milho + crotalária e milho + feijão-de-porco. A capina aumenta o Índice de Valor de Importância (IVI) do falso massambará (Sorghum arundinaceum) no monocultivo, enquanto para o apaga-fogo (Alternanthera tenella colla) a adubação promove controle eficiente. O consórcio com a mucuna preta favorece o aumento do IVI do camalote (Rottboelia exaltata), já o consórcio com a crotalária favorece o falso massambará (Sorghum arundinaceum). As plantas de milho em monocultivo apresentaram maior altura (ALM) e peso de matéria seca (PMSM). Contudo, o monocultivo proporcionou plantas daninhas mais altas (ALPD), além de maiores no peso da matéria seca de plantas daninhas de folhas estreitas (PMSPDE). A capina no monocultivo elevou a ALM e o PMSM, apesar de elevar também a ALPD e o PMSPDE. O monocultivo com adubação com NPK na semeadura apresenta ALPD menor que o sem adubação completa; entretanto, o PMSPDE aumentou com a adubação. A adubação com NPK na semeadura no monocultivo eleva o PMSM. O consórcio do milho com a mucuna preta apresenta efeito semelhante sobre as variáveis analisadas em comparação aos outros consórcios avaliados, assim como os consórcios do milho com a crotalária e do milho com o feijão-de-porco apresentam efeitos semelhantes sobre as variáveis analisadas.

Corn is among the most cultivated and used cereals worldwide. The objective of this study was to survey the weed community in corn cultivated in monoculture and intercropped with different Fabaceae in different management systems, during the spring/summer seasons in 2011/2012. The following treatments were evaluated: corn alone with NPK at sowing and weeding; corn alone without NPK at sowing and weeding; corn alone with NPK at sowing without weeding; corn with Mucuna aterrima; corn with Crotalaria juncea; corn with Canavalia ensiformis. Weeding increased the Importance Value Index (IVI) of Sorghum arundinaceum in monoculture, whereas fertilization promoted efficient control of Alternanthera tenella colla. The intercrop with velvet bean favored the increase of Rottboelia exaltata IVI, while the intercrop with Crotalaria juncea favored Sorghum arundinaceum. Corn plants in monoculture had the highest height (ALM) and dry weight (PMSM). However, the monoculture had the highest weed height (ALPD) and highest dry matter of narrow leaf weeds (PMSPDE). Weeding in monoculture increased ALM and PMSM, despite also increasing ALPD and PMSPDE. Monoculture with NPK fertilizer at sowing showed lower ALPD than the treatment without complete fertilization; however, PMSPDE increased with fertilization. The NPK fertilizer at sowing in monoculture increased PMSM. The intercrop of corn with Mucuna aterrima had similar effect on the variables analyzed in comparison with the other intercrop evaluated. The intercrops of corn with Crotalaria juncea and corn with Canavalia ensiformis also had similar effects on the variables analyzed.

A ocorrência do fenômeno xênia, considerado como o resultado do cruzamento que se manifesta na primeira geração da planta mãe, há muito é conhecida. Entretanto, pouco é conhecido a respeito da contribuição do efeito do pólen no comportamento das sementes de mamão. Objetivou-se neste trabalho, avaliar a influência do pólen nas características físicas e fisiológicas das sementes de mamão. As sementes utilizadas foram provenientes de frutos dos grupos Solo e Formosa, oriundos de polinização manual, correspondente aos seguintes tratamentos: T1- Solo autofecundado; T2 - Formosa autofecundado; T3 - Solo x Formosa; T4 - Formosa x Solo; T5 - T3 autofecundado; T6 - T4 autofecundado. Foram realizadas as seguintes determinações e testes: número de sementes por fruto, tamanho da semente, peso de mil sementes, testes de germinação, primeira contagem, envelhecimento acelerado, comprimento da radícula, hipocótilo e teste de frio. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições, sendo as médias comparadas pelo teste de Tukey a 5% de probabilidade. Não se verificou efeito da origem do pólen nas características físicas das sementes. Para qualidade fisiológica das sementes não foi possível avaliar o efeito da xênia, uma vez que, observou-se a manifestação precoce da heterose.

The occurrence of the xenia phenomenon, considered the result of the crossing that is manifested in the first generation of the mother plant, has been known for many years. However, little is known regarding the contribution of the effect of the pollen to papaya seed performance. The objective of this study was to evaluate the influence of pollen on the physical and physiological characteristics of papaya seeds. The seeds used in the study were produced from hand pollinated fruits of the groups Solo and Formosa, corresponding to the following treatments: T1 - selfed Solo; T2 - selfed Formosa; T3 - Solo x Formosa; T4 - Formosa x Solo; T5 - Fruits proceeding from selfed T3; T6 - Fruits proceeding from selfed T4. The following determinations and tests were carried out: fruit weight, number of seeds per fruit, seed size, weight of a thousand seeds, seed germination, first count, accelerated aging, radicle and hypocotyl lengths, and cold test. A randomized complete block design was used with four replications and the means were compared by the Tukey test at 5% probability. No effects of the origin of the pollen were verified on the seed physical characteristics. The effect of xenia on the seed physiological quality could not be assessed because a premature manifestation of heterosis was observed.